Aw man, this puts my Canon HV30 more behind the latest tech. HDV camcorders are 60FPS and 1440x1080 max, but at least they don't have bad compressed quality.
Well, the H.264 encoder used by Apple isn't at all bad - I've certainly seen much worse implementations (for example, those of Panasonic used in their 2009 720p P&S cameras like the ZS3 / TZ7). For that matter, deinterlacing the 60i footage produced by the HV30 is much more destructive to the image quality than using H.264 (and not HDV) in the first place.
120FPS camera instead of 60FPS. Are they also going to double the microphone's sample rate?
When played back at nominal (120/60) fps for fluid motion, there would be no point at increasing the sampling rate (44.1 kHz). At playing back 1/4 speed, it could, so that you could hear for example the sound of for example bats played back at 1/4 the pitch. Otherwise, it'd be pretty useless.