It probably won't be too far off 11pm - the closing ceremonies are usually far shorter. Kind of says it all though that so far the most entertaining thing has been the speeches.
Is it just me or is the TV direction/vision mixing really missing the beat, cutting to re-frames, missing fireworks, using very poor shots during music? It's like everything is reactive to what is happening rather than having a script to follow in advance. Seeing scenes being reset, shots of bored looking people etc?
Also a massive "fan" of the commentary you can't here over the audience presenter/voice.