Who, if not the leftist geeks, would be wooed by a Linux reference?
The word "ubuntu" in Zulu means "humanity towards others." Mark Shuttleworth, a South African, picked it as the name of his Linux distribution. Clinton used "ubuntu" in the local language to make a connection with the humanity towards others that his foundation supposedly stands for.
It's like I said earlier, if Clinton said "We have a new vista ahead of us" in some blathering about the future his foundation will supposedly create, you wouldn't be thinking he's promoting Windows, would you?