Worldcon is a mix of (now) 80 years of tradition and local fanish culture. It's lit-heavy, but not by any means lit-exclusive.
There are also things that are unique, either to Worldcon, or in some cases a single Worldcon.
Masquerade and Hugo Awards are big, of course.
Film program is going to be big this year. Christopher J Garcia is screening his Silicon Valley Science Fiction Short Film Festival for us,
There's a serious academic program track, if you want to nerd out with researchers and scholars on fantasy and SF. It's being run with the support of faculty from UC Santa Cruz and UC Davis (I think).
The Fairmont will be party central.
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