Last time I used OkCupid, I can't remember anything that would actually require JS to work. Real time updates (for instance, in IM) wouldn't be possible, but exchanging messages, looking at profiles and answering quiz questions is perfectly doable without JS.

(I know I always sound like someone who hates JavaScript, but at least for the stuff OkC had two years ago, it's not really crucial. IIRC, you could browse user profiles with JS off, but IM didn't work with JS off.)