Un huh. You're behind again.
If you post on a thread at all, that's an automatic thumbs up. If you manually, so to speak, thumb it up, well, we can't have you voting twice, can we?
What happened, good threads lost out by being thumbed down one time, and noone was bothering to thumb it up. They changed it to eliminate this distortion.
I don't do either, by the way, unless my only purpose is to get a thread out of my sight. I do that to most of the word game type things, and it doesn't mean I really dislike them; I'm just tired of seeing them on my screen.