A while back I stumbled across a great video that introduces MonoGame and covers a little history on why it was created. It is a great high level overview of the MonoGame framework that I think is worth watching if you are interested in or using either XNA or MonoGame.
The video was created by Mike from gamesfromscratch.com. There is a set of tutorials with the video that can be found here: http://www.gamefromscratch.com/page/MonoGame-Tutorial-Series.aspx.
Of course, RB has a great set of MonoGame tutorials on this website that can be found here: http://rbwhitaker.wikidot.com/monogame-tutorials.