Coyote Blog references the kerfuffle about a Wells Fargo conference held in Las Vegas. To the extent actual business can best be conducted face to face (true in the Coyote's experience), this conference had to be held, and he defends Las Vegas as a choice. "There are tons of cheap flights there from everywhere."
I've heard that a lot, but that hasn't been true, in my experience. Since I went to Las Vegas last year, I thought I'd compare the cost of plane tickets I bought most recently. All but one were over similar time frames, extended weekend trips, with a focus on flight times over lowest cost.
Minneapolis: The highest, by far
Orlando: 314.35 (business trip, not over a Saturday night)
Las Vegas: 335.98
Kansas City: 283.00 (normally much cheaper, but I bought too late)
For whatever reason (probably lack of competition), a flight to Minneapolis is always a ridiculously expensive ticket. And aside from that one trip, Las Vegas was the most expensive city for me to fly to. There is competition, with at least two airlines, including Southwest, flying nonstop to Las Vegas.