INTEL IS AHEAD of schedule with Larrabee. Initial boards are going to be shipping to devs in November. Before you get your hopes up, these are not consumer parts, nor were they meant to be. Dev means developer, and chances are the epic MMO that you are whipping up in your mom's basement does not qualify.
The initial boards are meant to code against, and they will do that nicely. They will not be at the final clock, final core counts, or final anything however. If you want to get your feet wet, Intel should have a board for you in a few months.
Don't expect stunning performance though, Larrabee is a new paradigm, and that takes a long time for most devs to wrap their brains around. If you are just going to code DXxx or OpenGL, you don't need one of these.
If you are going to do something interesting, or write engine/middleware code, well you are probably already talking to Intel about Larrabee. µ
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