Well you really should one day! They're such an experience you can't miss out on :)
I actually grew up in a family that always goes to concerts so I've been to like, 9 or so, but I will see much more as I age :)
I actually saw them live at the Comcast Center twice; once in 2005 (when I was little so I don't remember much), and then again in 2009! :)
I can't wait for their new CD coming out this year!