I've tried CyStats, Statpress, and Wordpress.com Stats (currently using Statpress), and I'm starting to get the idea that I'm getting underreported visits.
An article of mine got a heavy bump from Reddit, with (when I checked) 624 upvotes so far, plus some Diggs. All told, I'm getting reported maybe 200 visits since it went up yesterday. I realize people will Digg and upvote things without reading, but people also read stuff without voting, so that doesn't seem likely.
What gives? I have WP Super Cache going. Is it possible that this is screwing things up for me? Maybe it's not reporting times the cached page is getting loaded?