Nope, not yet. I haven't jailbroken it yet as it doesn't seem so necessary when you can get the most important app (MSN) through the browser (
meebo - online web IM for AIM, MSN, Yahoo, Google Talk messengers, works kickass). The GUI is still great without a skin.
ipodtouchfans forum have some very nice skins. I might install one later. Not right now tho.