We are new to this as well. I have want to read The Ethical Slut as well it's highly recommended by many and it seems Jenny Block on YourTango.com mentions it often.
We have found that it made us stronger as a couple as well. I think it's a lifestyle that would help a lot of couples if they would open their mind and hearts to the concept. But humans in general don't seem very open to sharing much. such a "mine mine mine" mentality in the world today... I think personal insecurities play a big role in that