While I believe the number was probably legit (we had about 6,000 visitors from StumbleUpon today) I don't think it should count because so many of them were here for just a couple seconds.
Hopefully they bookmarked us and will come back and help us break the record again legitimately (as members and not guests) but for now I've reset the record to where it was at 979... which is still REALLY amazing!
Maybe BYC was added to the front page of StumbleUpon yesterday. A while back I did a little push in Random Ramblings for people to visit that site and write reviews of BYC so that it would end up on StumbleUpon's front page. I wonder if that ended up happening.
Again, I'm inclined not to keep the stats when we see anomalies like this (where there are a ton more guests than members), so I may set it back to Sunday's record.
I always check the stats, but I tend to discount the 'guests'. I want to see the highest number of registered users when I check those stats, that to me is more meaningful. Usually there are more guests than users.