I finally got around to picking up "ICO" yesterday for $17.99 at EBGames. If you want to know more about it, check out GameSpy's review here.
Now for my feelings...this game is by far one of the most real games I've ever played. Every character animation from Yorda's idle animations to the strain on Ico when he's holding onto Yorda to keep her from faling to her death, all of them are done to perfection. The shadow demons are infinitely more menacing than any other monsters seen to date on the PS2, and that's saying a lot.
The story is inferred more than told, but that's good. This is one of the few games where your attachment to the characters comes via the gameplay and not via the cutscenes. If you aren't completely committed to getting Yorda out of the castle by the time you get to the windmill, then you are seriously in need of psychological counseling. By the way, turn on vibration when you start a new game. When you are holding Yorda's hand to guide her around, you can feel her pulse through the controller. Now that's immersion.
There are a few areas where you may need hints (which you can get here) but the platforming aspect isn't too hard. The puzzle aspect is where the game is at. While the game is rated T for Teen, it's okay for all ages as far as I'm concerned.
A few tips from me: The circle button is your friend. If you find your self constantly wandering off of ledges, press and hold your circle button to walk. You'll have more control. You can light your stick by tapping your circle button next to a fire source. Find a save point after each fight...you'll be glad you did. If Yorda is in one of the shadow demon voids, stand on her, hold your R1 button, and move away from the void to pull her out.
It took be about 7 hours to beat the game. While I would have been pissed off completely if I had paid $50 for it, it was well worth the sub-$20 price I paid for it, and I'm looking forward to this team's next title, "Shadow of the Colossus."