this has been discussed internally. for a variety of reasons, testing the software on a remote machine is kinda painful, so we would still have the overhead of copying the executable back to the developer's machine. the more straightforward approach is just to buy fast desktops for all the devs. a desktop with 32GB ram, a top of the line consumer cpu, and a middling gpu is roughly the same price as a good ultrabook anyway.

also, c++ compilation doesn't scale perfectly with more cores. linking is still single threaded, AFAIK.