My first question is why, why would Microsoft opt to open a retail store? Microsoft is in plenty stores and online, plus they don't make or sell hardware. Oh wait, I forgot they make the Zune.
There is no way that they are going to be able to compete against Apple in a retail format.
Microsoft is going through an identity crisis. Are they a software vendor? Are they a hardware vendor? Are they a services vendor?
Which one is it?
Until they decide what they are, they will not succeed. They have become too big and their software too bloated. A retail store will not help them sell or convince people to purchase software.
The only way people will purchase their software is if it is on the computer they buy at the store. Otherwise it is just too complicated for the masses out there to deal with.