There aren't too many accuracies as such, but I wouldn't look up anything there to construct a detailed historical/political/religious argument (I mean like a detailed one from an essay or something), some of the articles do have a slant of bias.
I've also been told by a friend that looking up religion on the internet is useless (he says that stuff on Islam can be very unreliable written by Christians/atheists who think they understand what it is).
Overall, it's good for basic info. Check for citations. They may or may not be reliable (you know what the internet's like). It's a pretty good tool though.