Actually it's kind of crazy. I'm not sure what the sight range is but the attack range of the tempest they're showing is 22 compared to a coll w/range which is 9. The swarm host looks really cool too, man the games going to be so crazy again!
http://www.teamliquid.net/sc2/ Look for Day 9, you can learn a lot from his shows here: http://www.teamliquid.net/forum/viewmessage.php?topic_id=104154 if your terran Gretorp live streams with a lot of good commentary while he plays. http://www.livestream.com/gretorpsstream