re: high traffic. A buddy and I hosted the static parts of our privacy activism page youropenbook on github pages (it was initially all static). This was during the privacy scandal of spring 2010 and as our traffic really ramped up we sent a message to the github folks to see if they minded at all.

They gave the go ahead.

We served millions of pageviews, had a significant impact on the debate at the time, and github pages took it like a champ.