So here"s a turn up: Encyclopedia Britannica - that venerable, peer-reviewed and terribly old media source of knowledge - is to allow users to write their own articles, a la Wikipedia.

The news made me smile. A few years back, when I was working at the science journal Nature, colleagues and I asked experts to compare the accuracy of science articles in Britannica and Wikipedia. To our surprise, there was not much to separate the two publications. Our peer reviewers - each a leading academic expert - identified an average of four inaccuracies in Wikipedia entries and three in Britannica.

The results generated headlines, but not as many as Britannica"s reaction did. The opening salvo was "Fatally Flawed", a 20-page rebuttal of our survey that was distributed to journalists and the posted online. Next came a letter to Nature"s publishers, published as an advert in the New York Times, calling for the story to be retracted. The attacks worked. "How could a respected science publication make such a grave series of errors?" asked one commentator.

It didn"t matter that our survey was neither flawed nor in need of retraction (for those interested, detailed replies to Britannica"s criticisms are attached to the original story). Wikipedia was attracting attention and Britannica had profits to protect. It had been defending its position by claiming that Wikipedia"s anyone-can-edit policy was causing reliability problems. Our survey undermined that claim, so Britannica set out to rubbish the article.

But Britannica"s problems were not really about Wikipedia. And they"re not now. Britannica is a different beast from its crowd-sourced rival. It tries to be a source of record. For many people - journalists, students - it is. Wikipedia is not. And that"s fine. Wikipedia remains a great way to get the gist of an idea (almost any idea)... but not the place people should turn to for fact-checked names and dates.

It"s like the difference between blogging and journalism. Many blogs are insightful and well-written. They"re also free. That scares some journalists, because it"s the type of content we"re paid to provide. But most bloggers, particularly those working for free, don"t want to report, check facts, provide balance or do any of the other things that good journalists do. They don"t have to, because blogs don"t replace news stories, they complement them.

That"s why reporters aren"t turning all their news articles into blogs, and why Britannica should not react to Wikipedia"s rise by letting the masses contribute. New media and old have different strengths. Britannica"s value lies in the fact that it"s expert led. Diluting that asset seems an odd way to proceed.

Of course that"s easy for me to say: I"m not responsible for Britannica"s subscription sales, which have presumably been hit by Wikipedia.

And there"s the root of the problem. Wikipedia is not Britannica and most blogs are not well-reported news journalism. But the existence of both new formats threatens the finances of those that preceded them. Right now it"s not clear where the salaries for professional writers, journalists or encyclopedia editors, will be come from.

The Washington Post won six Pulitzers this April; a month later it announced a 40% drop in profit. I"m sure that the people who run the Post are worried. But I"m hopeful they won"t dilute the qualities that made the paper famous.

It"s a shame that Britannica seems willing to do so.

• Jim Giles is a science writer based in San Francisco

There"s a direct correlation between the shortening queue of Brazilians in front of me and my rising sense of panic. I"ve come to the poor outer district of Retiro to meet Mae (Mother) Stella, a revered leader of the region"s Afro-Brazilian religion, Candomblé. She"s a gentle-looking 84-year-old, but she is held in such high esteem in the Ilé Axé Opô Afonjá compound that I am terrified of making a faux pas. Or I should say another faux pas: I"ve already made one by arriving in trousers, causing someone to run to fetch me a billowing African skirt.

I"m here on the advice of a local psychologist called Lucia, whom I met through hospitalityclub.org. Although she can"t join me, she recommended the centre as offering a genuine, non-tourist-driven ceremony, which she has attended many times, "out of curiosity, and because it feels good".

However, with no host to translate from Portuguese - or Yoruba, the enclave"s second language - all I can do is watch and copy. The congregation takes turns to lie face down on a dusty carpet and point their bodies at items around the altar - a conch shell, maracas, a giant root vegetable and finally to Mae Stella herself.

My turn comes and I do my best to follow suit. "You are blessed," whispers Mae Stella, and I breathe a sigh of relief. In truth, I"m slightly disappointed the ceremony hasn"t included the infamous Candomblé act of casting out bad spirits in a body-convulsing trance, but, nonetheless, I leave with the undeniable thrill of having been the only non-local in attendance.

In times when it can seem like tourism has left no stone unturned, a good shortcut to more individual travel experiences is hospitalityclub"s groups page. It offers no shortage of inspiration, and you can find a local host who shares your special interests or who can introduce you to something new.

It was while browsing hospitalityclub"s families group that I came across Lucia, whose profile says she "loves to travel and meet new people" with her husband and five-year-old son. "You are welcome!" was her instant reply to my request for accommodation. "You can stay for week, or for a month."

As if that wasn"t generous enough, I later find out that Lucia is agreeing to host me, despite being midway through chemotherapy from breast cancer. "Tomorrow is my next treatment, and my 40th birthday," she tells me, when I turn up on her doorstep in the beach suburb of Pituba. Surely this isn"t a good time to be hosting an unknown traveller? But she insists she likes the company.

The next day, the family hosts a low-key but upbeat birthday party and everyone makes me feel welcome, especially her husband, a leading member of Brazil"s communist party, and their son Theo. "I want to speak to her more, but all I know in English is numbers and colours," Theo tells Lucia with sweet earnestness.

My second contact is 24-year-old Fernanda from yowtrip.com, a promising new site aimed at helping travellers plan trips using local knowledge. I ask her if she"s willing to show me around for an evening. "We can surely meet," she replies. "Call me and I will come to pick you up."

She and her sister, Mariana, a fellow yowtrip member, take me straight to a hip Japanese bar and restaurant, Barthô. It"s owned by a friend of theirs and in what they describe as the "alternative and open-minded" Rio Vermelho neighbourhood. After getting our fill of temaki rolls and people-watching, we move on to the equally stylish Agua bar in Bahia Marina, where we sit until closing time, drinking caipiroskas - the sexy Brazilian way of saying vodka with fruit and sugar.

Next evening, I get a different slice of Salvador life with couchsurfing.com member Fausto, whom I found on the site following a word-of-mouth recommendation from a Hungarian site member I met further up the coast. A 32-year-old public relations officer, he has hosted over 30 travellers and says his favourite place to take guests is São Joaquim market. "I like to see how they react to the mayhem," he says.

However, for me, he has a different treat: the less-visited Ribeira neighbourhood. It"s an area that used to be home to the city"s upper classes, until they abandoned it after the poor moved to the opposite bay and spoilt their view. What remains is some of Salvador"s most beautiful, if slightly dilapidated, architecture. It"s also home to the city"s best ice cream, according to Fausto, and one trip to a 1930s parlour, Sorveteria da Ribeira, leaves me more than convinced.

Fausto, like all my Salvador contacts, is insistent that I come back in February for carnival, a time of year when he typically receives over 40 couchsurfing requests. As it"s often tipped as the world"s best, surpassing even Rio, I"m tempted and, right now, could think of nothing better than celebrating the occasion with Lucia back in good health.

However, before I start fantasising about return visits, I have one last stop, Buenos Aires. Is it possible to throw a party in a foreign city, with guests you"ve invited through travel-networking sites? I"m about to find out ...

vicky.baker@guardian.co.uk

Felipe"s beach tips

Morro de São Paulo A small car-free island two hours by boat from downtown Salvador.

Itacare A paradise for surfers and nature enthusiasts. Some beaches are only accessible by hiking through part of the Atlantic Forest, an experience in itself.

Litoral Norte You can still find beaches without any houses, hotels or electricity close to Salvador along the north coast. Drive towards the sand dunes at Mangue Seco.

Porto Seguro This is where the Portuguese first landed in Brazil. The beaches are great, and the town is famous for its nightlife.

· Felipe Coimbra is the founder of yowtrip.com