http://dvice.com/archives/2010/04/why-most-green.php
I would copy and paste the article, but it has a bunch of pictures and what not. Its a pretty good read.

http://dvice.com/archives/2008/08/esl_the_newest.php
Click the link for the picture of the bulb. From what I was reading, it sounds like these bulbs will be about the same price as the CFL bulbs. And these don't have mercury vapor in them and they are dimmable. I'm definitely going to buy one of these for my flood light outside. It'll probably last years upon years before I'd have to replace it again.