Oh good, I'm not completely dumb then, that's what I thought they were. Sheesh, I should have more confidence in myself!
Anyway, back to the idea, I think that would be an ok idea except for the fact that someone might want to just scroll down the nicklist and look at the info...not hover the cursor over one specific nickname and wait for the info to appear. So like, you want an overview of all the info on all nicknames rather than an individuals info, tooltips can't help you there, you need the info displayed easily.
My 2 pennies.