Originally Posted by
theblackbullet
I am a proud owner of HplusSon SL42's laced to tiagra hubs.
IIRC they weighed in under 1800g. They are the most responsive, most comfortable wheelset I have ever ridden. I also beat the hell out of them on a daily basis. lol
aaaaaaaaaand
I've raced them...successfully 
1) on who's scale? Published weight for the rims is 615 grams. So that's 1230. Shimano's tech literature puts the Tiagra rear hub at 426, and the front at 212. 64 spokes a 5 grams each, and 1 for the nipple (which is a reasonable estimate not know ing your spokes) gets you to 2230.
Which gets me back to the wheels are a fashion statement (and they look really nice in that pic.)
2) as for racing, it's the motor that matters.