Well, one great free piece of advertising is Adam Duritz's (of Counting Crows) rave about the show on his blog:
http://adam.countingcrows.com/journal.php?uid=2325 Though I did want to see the show, it wasn't at the top of my list on my once-in-a-blue-moon trip to NYC this past week. Thankfully, though, my friend bought tickets so we went. I'm so glad I did! I loved the show. I'm still thinking about it a week later.
Oh, and, yes, I'm a huge CC fan and so I was somewhat swayed by Adam's posting. It was the most I'd read about the show and stuck with me so that I certainly didn't protest when my friend invited me to the show. Hopefully other CC fans will take the recommendation and go see the show!