Some friends of a friend started a geographically-oriented business review site, Yelp.com, with an apparent emphasis on restaurant reviews (but an ontology supporting very many more categories.)
I've joined on her recommendation, and have been surprised to discover just how useful it's been already: I've found some nearby places I'd never considered before, and am now using to drive some of my purchases at local specialty shops.
Now, whether Yelp is another Next Big Thing remains to be seen. It's a closed system, with no apparent provision for RSS syndication of the content we the users add to the review base, and relatedly, no leveraging of microformat standards such as hReview, a serious issue (thanks to Mike Linksvayer for pointing me to this recently.)
Yelp seems to have purchased a GIS-oriented business database, and coded some Google Maps integration into their interface. Rather nice, but entirely US-oriented, with no indication they're ready to scale into the English-speaking markets of Tokyo (big expat and traveller population) and other locales.
Speaking of which, I just tried inviting a good friend, an American living in Panama who could be a productive member of the Yelp community, and he sent me back this, reprinted with his permission:
'Hi Russell,
These morons ask for a zip code and won't accept my sign-up without one. I see this sort of shit all the time. When are US geeks going to get a clue the the US is not the world and that not everyone who has internet also has a "zip" code? So Thanks, but no thanks. I won't sign up with jingoistic idiots. Please feel free to pass along my exact words, if it pleases you.
Regards,
Sandy'
Wow. Well, he does have a point. I see this as one of those "We weren't planning to be so successful" scaling issues. Can't count the number of times I've seen this. I think the Yelpers really should have generalized their GIS integration to allow world-wide registration, from the very beginning. I have lots of friends in Europe, Asia, and South America who won't be able to join due to this and related issues. Maybe agitating in the Yelp forums about this might help; I've noticed they do tend to pay attention to issues of interface (e.g. marking businesses as closed or moved) so they may listen. Of course, they may be planning some kind of world-market rollout, but it would help if they advertised that somewhere prominent.
In the meantime, I'm going to use the hell out of it until and unless it ceases to be interesting. It's a much more convenient place for me to bulk-load all those pictures of food and storefronts I take in my travels, more so than the Movable Type blogging interface I'm using here, and since most of my reviews are locale-specific, it's probably a better place for my rants and raves about local businesses (and ones I visit in other cities.)