CR / Poly
Having stayed at both the Polynesian and the Contemporary and if choosing just one hotel to stay at, I would stay at the Poly.
It's not that I did not enjoy my stays at the CR but the Poly theming just seals the deal for me. Here is my view on the resorts.
At the poly you really feel like you are in a tropical paridise. Though the trimming of the vegitation and removal of the birds in the GCH has taken away from the character of the building somewhat, the rest of the resort makes up for it. The eateries, shops, and new pool are all fantastic. I just wish Tangora Terrace was still around! The surry bikes at the resort seem more fit for the Boardwalk but don't intrude too much. Rooms are nice and because there are the different buildings you often find the location of each to have it's own benefits. The castle, pool, marina, or monorail view they are all nice and welcoming with something to see. That is unless you get a room with a big tree outside your patio door. This family likes to eat at 1900 Park Fare sometimes so it's nice to walk over to the GF, and the TTC is next-door for easy transportation to Epcot. Getting to DD is sometimes a bit harder, busses are often full and run off schedule. Cast members are also great, most all are friendly and willing to chat it up a bit or just say "aloha" as they pass by. The tiki torches provide for a nice soothing walk to your room after a trip to the parks or day of relaxation.
The CR does have it's benefits though, my favorites are the Concourse Steakhouse, proximity to the MK, and the large arcade. Even with it's somewhat high prices, I have yet to have a bad meal at the steakhouse. The arcade is a hit with kids, big or little, or even those who just want food on the run. Chef Mickey's is also a big hit for me, I like it better here than in the Marketplace. The rooms are not the same suttle colors they used to be. They have light tan walls with a purple and white zebra-like headboard spanning half the height of the one wall. Bedspreads are a bright red, purple, and yellow art deco fashion with touches of black, green, and purple spread throughout the room. Fireworks views off the 4th floor of the tower are a nice advantage too.
I think the CR has become a bit more modern when it comes to the rooms but the shops under the monorail, and hallways of the wings could use a touch-up.
That's my .02.