Did you have to give them your projected swim time? You'll get a start order, and each person will start a few seconds apart.
I just found out my HIM is doing a similar (though slightly different than a tt) start as opposed to waves. I'm nervous about it, but I think overall it *should* help with the craziness of the start.
I'm considering registering for it, so I haven't had to give anything yet. I was just trying to figure out what the time trial start meant. That sounds much nicer than the wave start!!
This race is one of a series of 3 - sprint, Olympic and HIM - and all 3 are doing the TT start.