It seems I'm not able to use them yet, so I can't give my full opinion, but they seem to go in the opposite direction of the simplicity of the Like system.
Ahhh, I see.. you have four posts to go... but I think it's safe to say you're not a sig spammer so I'll up your usergroup manually (thought I'd done it already to be honest!)
w00t! yeah, I don't even plan on adding a signature anyway. People who care know who I am (and some people who don't care)
Hahaha! That's exactly what I was thinking. I was clicking the cute little icons frantically instead.
Update: Added a couple more icons to the ratings. Chill pill and coffeecup icon (take a break) are the new additions.