So far I've managed to get irrecoverably stuck in SAB three times this year; I can't remember it ever happening before:
In bee-dog form during the race, I got stuck in a cloud. This was the most irritating because there's no waypoint there, no exit button, /gg and /stuck don't work, and logging brings you right back into the cloud. I had to go into wvw, then into Lion's Arch, to get out.
Got stuck inside a checkpoint in world 2-2 after activating it. /stuck doesn't work, had to /gg and give up a life
Got stuck inside an infantile cloud rainbow in 1-3. Same as 2, had to /gg and give up a life
I dunno if there's anything really different this year or I'm just having bad luck, and maybe there's nothing that can be done. Would be nice if /stuck worked here though. And if you had a way to reset in the hub.