Buy XP now, get "express upgrade" to Vista

[Dan <dan27649@xxxxxxxxx>]

This appears to be one of those really murky waters things.

Does anyone have a reliable source of information that shows, if I buy XP
Media Center, that I will get the Vista Home Premium edition as a "free"
upgrade?  Specifically, I am looking at TigerDirect's "Microsoft Windows XP
Media Center OEM w\Express Vista Upgrade" (see this
link<http://tinyurl.com/2o6r2j>)
The "free" moniker seems to depend on the vendor; TD is telling me that they
won't charge additional for the upgrade -- S/H still apply.  I chatted with
a TD rep, and called two different phone reps, and got three different
answers.

Maybe someone can recommend a better vendor for this type of deal?

TIA,
Dan