The original plan was to launch the new GPU from Intel with 80 cores but manufacturing process and TDP issues have reportedly cut the number of cores down to 48.
And that's not the only problem, it seems Intel is also having problems with parallelization on 48 cores:
The second part of the story is that it might not be that easy to put all 48 cores in use, not to mention how tough would it be to keep 80 cores busy all times. Intel will naturally want to use Larrabee for CUDA and GPGPU like general purpose processing as it wants a piece of this potentially profitable market.The first Larrabee chips are expected in late 2009 or early 2010.