I dunno which OTA update you guys are talking about, but I had an OTA update applied on my phone the day I received it, and was still able to root using the unrevoked method.
Anyway, I would HIGHLY recommend rooting the phone, and flashing a custom ROM. I'm using Fresh 0.3 right now, and the crashing issues I had are completely gone, and my battery life has GREATLY improved.
Here's the tutorial I used... Very easy to follow, even if it has a lot of steps.
http://forum.xda-developers.com/showthread.php?t=701004