Sp
Actually it is easy they will even transfer your luggage for you.
Vader's right, it's not much of an issue at all, but you may want the deluxe to be the latter half of the vacation. Not to sound like a snob, but the Value rooms are much much smaller than most Deluxe rooms, certainly smaller than the Wilderness.
You won't want to move into closer quarters after getting used to a little more space.
Three other suggestions
1: If the cost of upgrading to a deluxe is too much, even with a split stay, consider renting a car so you can easily drive to other resorts, have dinners or breakfasts there and generally be a lookyloo to your heart's content. Parking anywhere on WDW property (except the parking lots for the Swan or Dolphin hotels) is free if you're staying at a WDW resort, and that includes parking at the parks if you don't want to wait for buses.
2: See what rooms might be running at the Swan and Dolphin hotels. Though there are a few extra costs (as I said, their parking isn't free, and you won't be able to use Disney Magical Express to/from the airport if you're flying), and they won't be as elaborately themed as the other Disney resorts, you could wind up getting a much nicer room for not much more than a Value room. Plus, you're walking distance (literally 5, 10 minutes max) to the Boardwalk, the Yacht Club, and the Beach Club, and those resorts also tend to do up the holidays big time. You'll also be roughly 15-minute walk to the front of the Disney Hollywood Studios, which makes it easy to hope a bus to other resorts for the aforementioned lookylooism.
3: Some members of the Disney Vacation Club (Disney's timeshare) will rent out the use of their membership (their "points") during times when they can't go or need extra dough (like Christmas). There are websites that will help you handle the process and their commission is built in to the price of renting the DVC member's points, so no extra costs. A week in the DVC section of Wilderness Lodge would run you about 1500 compared to the rack rate of almost a thousand for the Little Mermaid rooms. And if you can could get a standard room at the Boardwalk, it'd only be about 100 more than that Little Mermaid room!
Granted, this doesn't take into consideration the possibility of any sort of awesome promotion that WDW might wind up offering (IF they offer one) and it's probably more difficult to cancel a trip on rented DVC points as you're then inconveniencing an individual versus canceling with the company. But that's not a bad deal for a week in a Deluxe resort.
