I always pronounced it "Ooh-Bun-too" I are deh n00b, and I use it
EDIT:
Heh, looked it up on Ubuntu.com and we were both wrong, but I was more right than you guys .
"How do you pronounce Ubuntu?
Ubuntu, an African word from Zulu and Xhosa, is pronounced "oo-BOON-too". See the other FAQ on its meaning, it's a worthwhile read, and no, you're not the first person to wonder. "
Ubuntu is an age-old African term for humaneness - for caring, sharing and being in harmony with all of creation. As an ideal, it promotes co-operation between individuals, cultures and nations.