I too picked up cheap tix to London for over Thanksgiving with my wife, 2 kids (14 and 12) and parents, and found the above info very helpful as this will be first ever trip to Europe. I probably erred by choosing Gatwick instead of Heathrow which is easier to get to and from.
I checked rates at a number of Hilton properties in and around London, all of which seem high for what I thought was off-season. What are the chances that rates will drop to more reasonable levels as the travel dates draw nearer?