The wheels are the standard Matrix 550 that comes with the trek 7100. As I said, I had them re-laced to a 4X pattern about 18 months ago. I've gone from 360+ to 330 on them and I have used them to support the bike, full panniers and myself (I waited until I was down 25 pounds to do it though. My last 3 rides I had only myself, water bottles and the emergency repair kit on the bike. I also pull a trailer onthe bike fairly regularly.
I think I want to go to a 40 to 48 spoke bike rather than mess with hand built etc. for a few reasons.
1) It will get the job done
2) When I load the bike down for overnight trips, I won't have to worry as much about popped spokes while I'm in the middle of nowhere.
3) Since I'm not after speed but endurance, the weight concern, although present, isn't what it is for a person riding a racing bike.