Depends.
I personally would not want to lose my PS3 and its library. But if you are done with the games and are no collector then sell it.
Selling it a week prior to Xmas should give you some extra money. When waiting to long you will have to "compete" with all the people that got a PS4 for XMAS and want to sell their PS3s.
You can always buy a PS3 again for less money than you sold yours.
So Id say sell it buy it back later and wait on the WiiU after XMAS when ebay etc is full of consoles people didnt want.













