I played it my first time all the way through without the patch. No problems at all. If you play a monk, however, you might want the patch. There were maybe three bugs that I found, and none of them are reported to be fixed by the patch (which I now have, after a tedious modem download).
"But I also made it clear to [Vladimir Putin] that it's important to think beyond the old days of when we had the concept that if we blew each other up, the world would be safe." -President George W. Bush, Washington, D.C., May 1, 2001