Last Thursday night I watched NBC's 30 Rock Live episode. Since I'm a Central time zone guy, I watched the East Coast feed. Early today I had a chance to watch the West Coast feed. (Both of which are located in their entirety at Hulu.com here and here respectively. Or watched below.)
Out of the two I definitely thought the West Coast version was funnier. While there were a couple of jokes I thought landed better and Tracy flubbing his lines in one scene in the West Coast version, most of the reason I liked it more boiled down to the fact that I could actually hear what was going on. The East Coast version had a hard time balancing the sound with the audience and the house band being too loud during most of the episode.
If you haven't seen them both I highly recommend it as they were both very well done and hilarious. Whether you've seen them both or not, you'll want to check out the first video posted below which features all the differences between the two version.
30 Rock: East vs. West
30 Rock Live: East Coast
30 Rock Live: West Coast