You're going to love it. I played the PS3 demo of the original LBP. It was awesome, as well. It's probably the best game that I've ever wanted, but didn't buy (one day, though......). The only difference in gameplay that I noticed was that there are only two plains of depth instead of three and that you can't control Sackboy's limbs independently like on the PS3.
But you'll have the demo soon enough. And, I'd wager that after playing the demo, you're going to buy the game!