I am going to flat out say that the GCH is the ONLY Disney hotel (on the continental U.S) to provide a true "Deluxe" experience.
I think it is better than the Grand Floridian, from pictures I've seen and accounts I've read of stays there. Although, to be fair, I've never personally stayed there.
We stayed at GCH, concierge level bunk bed room in October 2007. For comparison, I've stayed at WL (as recently at Feb 2007 but also for my honeymoon in a honeymoon suite). I've also stayed at Contemporary, as far as the Deluxe hotels at WDW go. I've also stayed at a standard room at GCH.
The GCH excels in the following areas:
-Pool area: the chaise lounges have terry cloth covered THICK cushions on them. ALL the chairs! They have a pool bar and waiters who come around to take your order, and they deliver the drinks to your chair. The pool area is enclosed by a gate, and requires a keycard to enter. Keeps all the "pool hoppers" and locals OUT. WDW needs this at their pools...In addition, the pool at GCH has a panoramic view of Paradise Pier. While you are swimming, you can literally see people riding the roller coaster and sun wheel. At night, it's stunning. However, it's completely private from the other side (i.e. people in DCA can't see you). I don't know how they pulled this design off.
-Room amenities: The beds have down comforters, triple sheeting, and everyone gets turndown service. The towels are fluffy and nice. The beds are comfy, even the bunk beds, which are much larger than the ones found in the WL bunk bed rooms. The closet is large enough to set up a pack and play and then CLOSE the door, which is great when you have an infant who needs a quiet place to sleep. The rooms are wonderfully soundproofed, both in the walls and the glass used on the patio doors. Even with a theme park view, when you close the door, you hear NOTHING. That can't be said for any WDW hotel I've ever stayed at.
-Concierge: The concierge lounge here is very nice and well set up. The food is FABULOUS! The selection of fresh fruits and vegetables, artfully cut up and arranged, was especially good. I loved that they never ran out of food and people were civilized, for the most part. There was no hoarding of or attacking the food, as I've heard happens at some other concierge lounges. At night, they had hot food offerings from Napa Rose and the desserts were works of art! They also had nighttime entertainment in the lounge. There was storytelling in pj's (kids were encouraged to come in their pajamas and bring their pillow...it was cute). There was also a guy who played a guitar and did sing a longs (again, a little pajama party). They served hot cocoa and cookies to the kids during this. It was a nice touch and very fun.
-The Lobby: There is a huge fireplace that is better than the one at WL, IMO. It is actually a "hearth" and you feel like you are sitting INSIDE the fireplace. It's very cozy and there are even kid sized rocking chairs. In addition, the piano player at the GCH is awesome. There are a couple, but what I love is that they play piano classical versions of Disney tunes. It's very sophisticated, but still has that Disney touch. The lobby is just as nice as the WL. In my opinion, it is just as themed. However, the theme is a bit more obscure. You are supposed to feel like you are in the redwood forest, and the exposed beams of the walls and ceilings creates a tree canopy (trunks and branches) effect if you really look closely. It's visually interesting while at the same time not being as "in your face" as the theme at the WL (which I also love, by the way). It's a very classy lobby. I love the floral pattern in the marble floor and how it runs into the rug. When viewed from above, you can hardly discern where the marble flooring ends and the rug begins. It's really neat. This lobby is a favorite place of mine to hang out to relax during my day trips to WDW. It's so nice and cozy, and usually empty!
-The Spa! The Mandara Spa inside the hotel is worlds above and beyond the spa at the Grand Floridian. Perhaps this is because it is run by an outside company, but I don't mind. I did not get the same aloofness and snotty attitude that I got from the CM's at the GF Spa. And, for what you get for the money, the Mandara Spa is so much better.
People comment about the lack of grounds. There are two courtyards in this hotel. One of them is HUGE and grassy and features walking paths and floral arrangements, as well as benches to sit down. The other is a circular one, where the monorail goes by overhead. While not as large and expansive as some of the areas at WDW hotels, there is actually MORE outside space at this hotel than at the WL (if you don't count the trail to Ft. Wilderness) CR, and BWI and certainly more than AKL.
In general, I find the service and atmosphere to be superior to that at the WDW hotels. I really think that they hit the nail on the head at GCH in terms of what a Deluxe hotel *should* be...