Google+ vs. Facebook

I just stumbled upon an article about Google+ vs. Facebook - and I must say curiosity got the best of me.  I signed up for it, and it is strikingly similar to the new layout I saw on FB this morning.  Is anyone out there supremely educated on the differences between the two?  Or what the benefits of using one vs. the other would be?  I'm curious, and nosey!  I don't want to miss out on all the buzz!