Anna
You are off on a family holiday to Orlando this September (2006), then this booking you are talking about here (Contemporary/Grand Floridian) is NEXT October (2007) isn't it?
If I was you, I would go with your heart on this decision and then leave your hotel plans as they are. THEN, go and have a BIG tour of all of the resorts (Grand Floridian, Contemporary, Beach/Yacht Club and anything else you may fancy). Explain that you are back in October 2007, "really like the resort you are looking round, but could you someone show you a (preferably) concierge room and maybe the concierge lounge too?". They should be able to do that. That should make it easy for you to make up your mind... That is what I would do.

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I find it kind of odd, because the resorts that you have booked so far for the Oct 2007 trip (Dolphin, Poly, Contemporary and maybe Grand Floridian) are all SO different - would be surprised that anyone would REALLY want to stay at all of them (and not have any strong preference for some over others).
I think this is the trouble with booking so far in advance. We book about 6 months in advance. I do lots of thorough research, book it and generally that's that. I trust my own decisions and don't want to waste time and energy rehashing my thoughts and making changes.
Boo