Be careful about the tempurpedic beds guys!
First of all, the mattress salespeople are every bit as bad as used car salespeople--in general, that is. They'll pressure you to buy right away, and use other high pressure sales tactics, and they'll leave out important bits of information about what's involved if you don't like the beds.
My brother and his wife bought a Tempurpedic mattress and really didn't like it, and had to pay extra money that they hadn't expected or been told about when they wanted to exchange it.
There's a lot of information on the web about these, and even a website by one guy who got screwed over on the whole deal. Some people love them, it's true. But not everyone by a long shot--that's for sure.
DO YOUR RESEARCH.
Because, it's a helluva lot of money to spend on a slab of foam! You can get other brands of memory foam beds for a lot less. There are some good webpages on memory foam, and the differences between memory foams, and guides to help you determine what you really want and so on.
Personally, I prefer two to three inches of good memory foam topper on a nice firm regular old spring-mattress. I recommend the toppers sold at Target and Wallmart that are 100 percent memory foam. (The thicker one(s) at Wallmart are combinations of latex w/ memory foam). They are about $50 to $75 IIRC. We have two of them (one from Target, 2 or 1.5 inch, plus one from wallmart 1.5 inch) on our bed, and to me it feels every bit as comfortable and supportive as the Tempurpedic beds at a fraction of the price.
Still, everyone's mileage will vary, and some people absolutely swear by their Tempurpedic beds--and that's great!--just be sure that you're one of those people before shelling out $2 to $3K on a block of foam, or be very sure about exactly the details for returning it if it doesn't work out for you.