Heh, yeah, it's frustrating. The website for reservations never threw an error, it just kept throwing "event not found" and when it finally did find the event, it was already booked full.
There's 5 hotels involved in this, two of them allow what they call "legacy booking," meaning people who've scored a room there can book a room for the next year (as long as they pay in full.) Those two hotels? Yeah, not even opening booking as they're already full-up.
I have loved some of the places we have traveled, but to know I want to comeback to the same place next year? I haven't done that yet. We are trying to not repeat places right now. Except we have done Hawaii for 5 different trips, but all have been different experiences. We are thinking we may repeat a place if we can't get the flights figured out on the one we are trying now.
Just makes me curious as to when and where you are going for it to be that popular.
As an artist who runs a booth at the event every year described it (and quite perfectly, too!) the convention could best be described as "Nerd Mardi Gras."
5 days (24hrs a day) of just about every geeky, nerdy, weird, crazy things you can think of... Costumes everywhere, and you can bump into famous (in their field) people anywhere. We went in 2018, I bumped into Larry Niven (Ringworld, Man Kzin Wars,) twice, Timothy Zahn once in an elevator, and the wife took a writers workshop run by Mike Stackpole (Star Wars novels, BattleTech novels.)
Panels on technology, futurism, medieval stuff, maker stuff, you name it. You enjoy gaming? The D&D role playing fills up as fast as it's announced, they've got consoles you can pick a game and plunk down to play, walk up and play table top stuff.
Parties? We (being old farts,) only managed two late night events, the 8-bit 80s party and the kilt blowing.
This con fills 5 downtown Atlanta hotels and pretty much every hotel within an hour gets booked. I think the year we went the attendance for the 5 days was around 80000 people...
Way, way, way too much fun. If anyone's interested, I've got a shared Google Photo album, I can post the link to our photos later.