The Patapon 2 demo is up on PSN, and it's a pretty good demo, and pretty long.

A few other points:

1. You can load in your saved game from the first Patapon game. You don't start with all of your old equipment, but you start finding your old items later in the game. I haven't found any of the unique items from the first game, though. You also keep  some of your Ka-ching (money), food, and materials, so you don't need to grind through levels as much to build up an army.
   
2. Saving the game after the demo will keep you from having to replay the first few levels when the game is released.
3. The game now has difficulty settings. The normal difficulty setting seems more forgiving than the first game was. If keep the rhythm going, you will enter "fever" mode. Your attacks will do more damage and your units will take less damage. In the old game, losing the rhythm would drop you out of "fever" mode immediately. In Patapon 2, you can stay in "fever" mode even if you lose the rhythm once. It will warn you that you are about to lose "fever" mode and give you a second chance.

I dislike it.