I'm on a Mac running OS X v10.6 (Snow Leopard). I have Mercurial 1.1 installed.
After I hit Esc to exit insert mode I can't figure out how to save and quit. Hitting Ctrl + C shows me instructions that say typing "quit" will write and quit, but it doesn't seem to work.
:q[uit]
quits.
:w[rite]
saves.
:wq
is a shortcut for both
:!command
runs a command in a shell (you could use this to commit without having to leave Vim)