BSLeVan: SPL has some pretty good advice... I'll throw in some potentially dissenting opinions however.
I run Shimano R500s on my road bike. I don't really race, I do a 'fun' race ride once in a while. I hover between 230 and 240 pounds and Haven't had an issue with them yet.
At one point I quizzed shimano on their Custom wheel philosophy, since they do seem to have a trend towards lower spoke counts than a heavier gentleman such as myself would be comfortable with normally.
Their claim was that their wheels accross the board are designed to be as strong as a traditional 32 spoke 3 cross wheel. My experiences with them so far lead me to agree...
That said the main disadvantage of 'botique' wheels in general is that they sometimes use exotic parts (Straight pull and/or Aero Spokes) that can be a pain to find at many shops. And when you -do- have a rim failiure you are stuck buying a whole new wheel typically.
I couldn't give you a very strict reccomendation without knowing more about your setup, but I'd look into Open Pros with 105 or Ultegra hubs laced in. The Ultegras aren't really much lighter but if you get a good deal on them go for it...
Also, Dura-Ace 7800 Rear hubs will only take a 10 speed cassete so that's out the window anyway.