I just attended my first WordPress WordCamp in Phoenix Arizona at the Arizona Grand Resort. There were around 500 people at the event. The event was great!
The speakers included: Alon Waisman, Lorelle VanFossen, Dave Moyer, Jim Christian, Matt Mullenweb (founder of WordPress), Joshua Strebel, Chuck Reynolds, Jayson Cote, John Hawkins, Merlin Mann, Brent Spore, and Clintus.
What was clear to me by what I could hear from some of the attending participants questions is that the broad use of WordPress in commercial situations is a wide open business opportunity.