Add me to the list of people who really like psionics. Given the chance, I'd like to dump spell level systems (vancian) and go with psionics - or some type of "general pool" system. These might encompass ToM ideas, too.
In general, the tip above about making sure they stick to their manifester level is important. Personally, I've not had many people play wilders because their known powers are so small - so I don't know if their special abilities to overchannel are broken or not. I do know that I've also seldom seen Overchannel in a game, so psionics works just fine if you eliminate that feat. Especially if you are worried about it.
From what I've heard, 3.5 psionics is way better than 3.0 psionics. I've only ever played 3.5 psionics, and I consider it balanced with both a wizard's versatility and a sorcerers pure power. So, read over the 3.5 rules with a clean slate - because I've heard the differences between 3.0 and 3.5 are significant.
Also, I agree with the above comments about making sure to have elongated encounters - or preferrably a minimum of 3 to 4 encounters - per day. It is easy for psions especially to nova, but this is really only truly game breakingly noticeable at levels above 10. Before that, I think the power of a nova is still manageable by a good DM. And, if a player ever does nova, make sure to roll frequently on the random encounter tables!
In sum, though, give them a review. They're really worth a good read.