It should run just fine in it's own as long as you have the latest patches and updates offered by Battle.net when you first login to the client. If you have any other issues while running the game in Windows Vista than you can always check 3 thing's to make sure your game play is smooth.
1.) Run your video test, and make sure nothing fails.
2.) Right click on the program icon and set permissions to Administrator.
3.) Right click, properties, compatability, and set it for XPSP2.
With those steps in mind you should have no problems running it at all.
That's still in debate Zoltar, I have no knowledge do discredit that fact or prove, I am only going on when I was beta testing it, the first boot screen and boot info used was Windows XP, and not Vista, eventually they took out all the boot info and the boot screen during beta testing, and made it all blank. So my only conclusion is to say that they were building off of the XP platform while making this version.