I'm not going to list all the pros and cons - that has been done very well already. So what I will say is this - as an average adult gamer, one who plays for a while an then loses interest for a while - I played Okamiden all the way through within a week. The story is INCREDIBLY well-written, and while the cut-scenes can occasionally seem a little long, I like that they can be skipped should you choose to do so. I love how the story actually explains quite a bit of what happened in Okami. And while the gameplay seems a bit simplistic at times, figuring out exactly how to fight each boss can be a bit tricky.
Overall, it's not often that I am affected by a video game, but there certainly a few tears shed at the end. Again, the story is perfect. I truly hope that this game sells well enough that a sequel will be considered. Okami was one of the best underrated games, and Okamiden is a terrific sequel.