It's a very hard one to call.
The new IPs I own are InFamous, Uncharted, Resistance and LBP. Coming soon will be Demon's Souls and MNR. Other than Resistance (because it's FPS and I only bought it because it was so cheap used) they all have a claim on being my favourite (OK MNR not too likely)
Oddly, because I've hardly played it, I think LBP is my favourite. And I think the way LBP2 seems to be shaping up it's really going to blow every other Sony IP out of the water. Hell, if you can make Uncharted: Sackboy's Fortune, SackFamous, Demon's Sacks (ewwwww sounds rude) and Sack-kyria Chronicles on LBP2 what else can compete?
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
Jimi Hendrix