I posted the exact same post when i just signed up, not knowing that there are SO many psots about tubeless tires. I agree do a search before you post any thread. Also check in the mountain biking section.
Tubeless are used maily for off road-riding, i dont know a lot about them but from what i've heard is that they are strong and you can set them to a low pressure for grip easily (like bac said).
Unless your into off-road i would bother with them, just get some stong tubes.