BUT (there's always a 'but' isn't there). I'm skeptical. On two fronts:
First, it's becoming increasingly difficult to make reservations as a guest in a nice place unless you're planning 4-6 months ahead of time. Some people have the luxury of doing that, many do not. I've just taken reservations for both Xmas and New Year's eve at my place in NYC and it's barely the end of July.
As a guest, this irks me. I spent 3 weeks in London recently, booked the trip about a month in advance, and tried to no avail to find a place on AirBNB -- nada. All the nice places had been snapped up months ago, and the ones that were left were either shady brokers or absolute crap (it makes sense -- I wanted a 3 week booking. If a nice place had even a 1-day booking in that window, the whole place was unavailable). I ended up booking on HomeAway or FlipKey or one of their competitors.
Second, I feel in some sense, the tide is turning the other way on the regulation front. I've been lucky with my place in NYC in that I'm in an AirBNB-friendly building and I've had extremely good luck in getting terrific guests. But the regulatory environment is not AirBNB-friendly and it's getting less so. Several people who used to host in NYC have stopped doing so for fear (irrational or otherwise) of running afoul of the law.
I tried to host w/ my apartment in SF and within 72 hours of posting the listing, I received a very strongly-worded C&D letter from the building's management company staff attorney. They had someone in the office who constantly scanned for listings on AirBNB and came down hard and fast. Others have reported similar stories from HOAs and management companies.
So of course I want nothing but the best for AirBNB - I've a happy customer on both sides. But I don't think it's such a slam dunk as many seem to think it is...