The sidebar with site stats at the right shows wrong numbers.
For starters, the 0 visitors/day is clearly wrong. I've already asked about it with respect to Area51 stats, but got no response in a month (how come?). This now is worse, it's the same buggy data shown on the main site page, even for users not logged in: that is, to everyone.
The other data seems to also be lagging behind. For example, it shows 1971 users, but user 1971 was added three days ago, and there is now user 1980. That may be explained by account deletion though.