i spent my new year holiday in hk in '06, and i do remember major sales at popular malls i've been to (langham, harbour city, times sq and ifc). you might wat to check out this outlet mall called City Gate too. I'll be in hk too for the late part of dec too, hope i'll have more time to check out the shops agian. :-)
If budget isn't a problem, I definitely recommend the Island Shangri-La. It is a beautiful hotel, with wonderful service and a great location. The pool is pretty nice too although at that time of year the weather will be questionable for poolside lounging.
Another great hotel is the Mandarin Oriental - which has great restaurants and is very convenient to shopping. Of the two, my favourite is the Island Shangri-La though.
If you want to be in the 'downtown' HK, you may want to consider staying in Causeway bay area. That's where the locals hang out and Times Square also located in that area. You'll find the designer boutiques inside Sogo or Times Square.
I'd recommend Park Lane hotel in Causeway Bay.
I love Hong Kong, it's like my second home. Enjoy your trip!
If you're interested in the whole shopping/dining experience, I recommend Lan Kwai Fong hotel. Its located inside a mall and their service is great. Its located in Central, and there's an additional upscale mall around the area and tons of really great restaurants. It's in more of a corporate location, so there's a bunch of buildings, but they do have a MTR station for easy traveling.
I think you should find a hotel in TST such as pennisula, langham, marco polo (inside a mall called harbour city). TST (Tsim Sha Tsui) is the middle of everything. Its on the Kowloon Island and its only 2 station (around 2 minutes ride) away from Central, where all the upscales shops are at. Tst has tons of upscale shops too but i find SA at Central are much nicer. TST is the place where most tourists are at so shops are really busy and you don't get much customer services IMO. TST is also close to MongKwok, a place where you can get lots of cheap stuff and you can eat some great local foods.
But where you stay in HK is really not big of a deal because the transportation system in HK is SOOOO convenient that it doesnt' take long to travel to anywhere.
BTW, if you want to go to the HK island from Kwoloon island, its great to take the ferry (located in TST) if you are not in a hurry. Its a lot cheaper (2 HK dollars approx. vs. 10+ dollars) and you get a great view of the HK skyline. Its also very relaxing on the ferry.