Wow. Ubuntu 10.04 puts the buttons on the left. How peculiar. Why?
It is easy to customize them, put them where you like. I prefer WindowMaker style, with minimize on left, close on right. This does it:
Caution: straight quotes are needed here, not the angled ones. The blog automatically changes straight to angle, which is a PITA.
gconftool-2 --set "/apps/metacity/general/button_layout" --type string "minimize:close"