I've done this trip (MLK) 4 different years (From Philadelphia). Sometimes it has been great, sometimes it has been less than fantastic. It seems that when I go, the snow turns on right when I leave.....argh!!! I now go over President's weekend and though its more crowded, the snow is so much better in Feb!!!
I went once to Mt. Baker in Washington (gets the same systems as Whistler) and it sucked! I hate to say it, because I know Baker, but the conditions did not warrant the travel time it took to get out there for such a short trip.
I would suggest hitting SLC. There are a ton of good resorts within 40 mins driving of town, Big Gnar Gnar for the experienced and mellow green/blues for the beginners. Plus, on your last day you can ride till 2 and still catch an evening flight back to the EC and still be home by midnight. You'll want to ride Snowbird, Brighton, and Solitude. If you want to go for a little exploring drive, you'll want to check-out Powder Mounain (lots of terrain and little amenities) or Snowbasin (even more terrain and lots of little bells and whistles in the middle of nowhere.)
Thats my two cents.
Traveling the States and Taking Pictures