Price alert: Microsoft is dropping prices on certain versions of its Vista operating system, starting with the release of Service Pack 1 in mid-March.

The upgrade version of Vista Home Premium will drop from $159 to $129, although pricing for the full version will remain the same. The full version of Vista Ultimate will drop from $399 to $319, and the upgrade version goes from $259 to $219.

You can already get a better deal on Vista from Amazon.com, where the Home Premium upgrade is selling for $95 and the Ultimate upgrade for $195.

But that's only a good deal if you want Vista. There are plenty of XP users sticking to that older, tried-and-true operating system, and plenty of Vista users "downgrading" back to XP themselves.

—Donna Tapellini