I did find this on blackberry's site... I'm actually a little mad that this is something that they couldn't provided! Most basic phones have SMS.. why not the 7510 BB?!?
http://www.blackberry.com/products/service/sms.shtml - look at the bottom you see this:
†The BlackBerry 6510, BlackBerry 7510 and BlackBerry 7520 support incoming SMS only.