I use it - don't know why to be honest, except it allows me to shame myself now and then by looking at the # of hours I play games :)
Raptr has been growing a bit though and also has some sort of reward point system (get points for playing games/doing stuff, earn enough points and use them of raffles or even buying stuff out right), they have come up with a streaming & video recording system and also have a record & replay feature (if your graphic card chipset supports it)
Nothing superbly special but it isn't too bad