Your biggest problem with Linux is the hoops you have to jump through to get most of the VSTi's running smoothly, Some do, some don't. YMMV. Plus, if you use hardware accelerators (UAD, TC Powercore) you may have a VERY hard time integrating those.

Linux shows a lot of promise, but unless the industry as a whole embraces it, you are going to have to get lucky AND geeky to use it as easily as you can use OSX or WinXP