Finished Shadow of the Colossus.
As a general "experience", it's definitely one of the best games I've ever played. It leaves a huge impression and excites the imagination wonderfully. It reminds me of Ikaruga in that it's one of those game concepts that's so simple and clever, it makes you wonder why nobody had ever done it before.
When focusing in on it as an action game, however...it's really just "OK". Personally, I think of it in terms of a 70/30 split; I found it boring roughly 70% of the time that I was actually playing it.
The long horse rides from the hub to the colossi could make me feel the atmosphere...the vast, lonely, beautiful, raw world of the game...about 30% of the time. The rest just felt like a waste. Watch a bland 3D landscape go by for several minutes. Hope your horse obeys your commands (they programmed him to disobey you occasionally). Do your best not to go the wrong way, or else it's up to a half hour of desperate wandering.
The 30/70 split applies during the colossi fights, too. In the beginning, I spend about 30% of the time eagerly studying the layout of the land, the movement of the boss, and what I can do to provoke him. The other 70%, I'm merely waiting for either the colossus or my character to get into the right position to try what I think might work. Later, when I've cracked his pattern and know how to kill him, I spend 30% of the time actively doing something to accomplish this, and the other 70% of the time getting shaken off and waiting for a chance to get near where I need to be again.
Ico was much better. You can set aside all the story and atmosphere, and you've still got yourself a totally decent puzzle game. Again, Shadow of the Colossus has one hell of a presentation, and I'm actually glad that it's held in such high regard and looked to for inspiration. I really appreciate some of its minimalism, too. It's just that the action itself is actually pretty milk-and-water.
I might play it one more time to see if knowing how to do everything in advance improves the experience.