Does Mountain Lion support Windows XP?
I have a macbookair running snow leopard and VMware fusion 3which runs Windows XP, If I upgrade to Mountain Lion will XP be supported?
MacBook Air, Mac OS X (10.6.8)
The issue for you is not whether XP is supported but rather is your version of Fusion supported. Go to the Fusion site and ensure your version will work with Mountain Lion. If it will you are all set. If it won't, upgrade to a version that will work or switch to another VM that will work with Mountain Lion. Once your VM works XP will work.
If you are planning to install XP using Boot Camp rather than in a VM like Fusion, Parallels, or VirtualBox, then XP won't work with Mountain Lion.