Here's a report on the mad, often fruitless scramble for hotel rooms in San Diego during this year's Comic-Con International. One of the commenters there thinks the con oughta move to Vegas. As I've explained here a couple of times, I don't think that will ever happen, nor should it happen.
As partial evidence in the past, I've cited the annual Consumer Electronics Show in Vegas. Now, it's tough to compare conventions in different venues because, for example, we have no firm idea of how large the Comic-Con would be if it did relocate to Vegas. Right now in S.D., it's around 125,000 attendees per con but that's because that's all the convention center can hold. Four-day passes are already sold out so it's safe to assume that if they had more floor space, as they would in Vegas, they'd have a lot more than 125,000 people there. On the other hand, we don't know how many people who eagerly go to San Diego wouldn't go to Las Vegas. Some folks don't like Vegas, especially when it's 110 degrees in the shade and there isn't any shade.
But consider the C.E.S., which is held every year in that town — in January, when the weather is more tolerable. Attendance got up to 145,000 or so for a few years there and hotel rooms were just as tough to get and just as expensive as they ever are for San Diego. Matter of fact, it's been suggested that some hotels deliberately jacked up prices to discourage C.E.S. attendees, who are notorious for not doing a lot of gambling. (The in-town joke was that a C.E.S. attendee comes to Vegas with one shirt and a twenty-dollar bill and doesn't change either one.) We can guess what kind of gaming profile the Comic-Con crowd would have there but I'd wager big that they'd wager small.
In any case: Late last year, with the economy doing belly-flops off the high board, there was a pre-C.E.S. panic that attendance would be way down. It was a huge news story in Vegas that any hotels were actually (gasp) dropping their prices during C.E.S. That was unheard-of but indeed, room prices at some hotels (not all) went from the astronomical to the semi-astronomical. As it turned out, attendance at this year's C.E.S. fell 23% from the previous year. 110,000 people attended.
I'm probably giving you T.M.I. here (too much information) but what I take away from this is that no matter where you go, if you have 125,000+ people attending a convention, rooms are going to be hard to get and expensive. I'm told that things should be a bit better in San Diego starting next year because (a) more hotels are opening and (b) there will be fewer "other" conventions in town.
In the meantime, if you tried to get a room for San Diego this year and failed, do not despair. More rooms should become available so check the site from time to time…and ask around, look around. A lot of folks make multiple reservations, then cancel all or all but one. Some people book outside the convention reservation system and then, if and when they get a cheaper or more convenient room, they let the less desirable booking go.
You might also consider taking the train to San Diego for a day (as I suggested here) and I should append another tip. Many folks have told me of the joy and ease of using the San Diego trolley system to get from the train station to the con…or from outlying hotels and motels to the con. I've never taken it but everyone tells me it's comfy and clean and reliable and cheap. Here's a website where you can see where it wanders. The con also, of course, has shuttle buses from many close-by hotels that will get you to the convention center.
Yeah, I know it sometimes seems like a lot of work to attend that convention. But once you get there, most folks seem to think it's more than worth it.