This is certainly an interesting concept. Access to academic and general interest books for a nominal rental fee. It's certainly an intriguing idea.
I had a NYPL out-of-state library card which cost me $100. That same $100 would allow me access to 20 books through this program, and I'm sure I didn't check out 20 books over the past year through NYPL. I'll certainly add the UCP website to my list of favorites.
Thanks for the information!