Flower is a GREAT PSN game. It uses the Sixaxis motion controls better than any other game to date. Sony seems to be giving up on this format as it hasn't been implemented as much as it should be. Check this review which explains things in detail.

http://www.psxextreme.com/ps3-reviews/221.html

If you like using the Sixaxis or are looking for a completely different gaming experience, then this game is a must-buy and worth the $9.99.

I thought about getting this the other day but MJ said it was... ok. I love the PSN games usually.