Sport Pilot License

[flipflops]

I've decided to get my pilot's license and I came across an article in Plane & Pilot that peaked my interest. It was all about Light Sport Aircraft, and how getting your sport pilot license is becoming increasingly popular. I'd like to be a flight instructor later on down the road, but this has really got me fired up. With that being said, I have a few questions

1. Can anyone recommend a good flying discussion board?
2. Anyone on this board flying LSAs and/or have their Sport Pilot License?
3. I read the cost is a lot less, but what is it?

Thanks!