The "alleged" snopes inaccuracy dealt with Australian gun crime statistics. In correcting an urban myth, they asked the Australian government for statistics. They then posted it on their website to counter the urban legend. After that, the Australian government (for whatever reason) corrected or modified their statistics. So snopes updated their page to reflect it.
This was what some people were waiting for, in order to jump up and scream that snopes was "wrong" about something. And yeah, snopes made the mistake of getting their information from an unreliable source: government. But for people to use this to say that they're inaccurate is kind of absurd. Snopes does the best fact-checking they can. They probably make an occasional mistake but their efforts are better than anyone else in digging into rumors and hoaxes.
I find it hilarious when people forward me (or post on chat boards) incredibly stupid things that they got in their email, and when someone tells them it's a hoax, they jump up and down saying that snopes isn't accurate. Well it's more accurate than simply forwarding stupid emails and believing them!!!
Anyway, I hope that cleared it up as to what the topic was that they were supposedly "wrong" about.