when web 2.0 attacks!
Plazes is pretty cool, but if you get the latitude and logitude wrong... suddenly Brisbane airport is somewhere in New South Wales: plazes.beta Plaze:Brisbane Airport/Australia/4007/Brisbane/Banksia Place.
Plus there are some limits to localisation - Australia does not have 'zip' codes, for example; we have postcodes. But then it probably doesn't matter - since most of our television is American, the average Joe probably does know that a zip code is like our postcodes. Plus I'm pretty sure they had to forward the phone number 911 through to 000 (our real emergency number). But I digress.
The real point to be observed is that systems are only as good as the information people put into them. Enthusiasm doesn't replace accuracy, nor does a person's willingness to enter information imply they'll proofread it first.
Still, it's fair to say that I am surprised how well community sites can work. You just have to be a bit cautious: is that Wikipedia entry accurate? ...or is the page in the middle of an edit war and someone just rewrote it with an extreme bias?
Web 2.0: remember, more signal means more noise too.