Looks like my team may be using a bit of it, so I'm going to start learning it.
Just returned from Powells Technical Books (best bookstore flat out) with a Ruby book. They were all out of them at OSCON, but still happily gave me the OSCON 35% discount. I didn't have my badge from OSCON on me, but I did have a Mozilla Firefox T-shirt on so they believed that I'm a hacker.
Upon the recommendation of my friend Erik, I bought Dave Thomas' Programming Ruby.
I'll let you know what I think as I learn. I know a lot of people who I respect who dig Ruby. I'm assuming I will as well. I doubt I will turn into a Java basher though (like a lot of the Ruby on Rails crowd), but one never knows.