Regarding the upscaling of the effects rendered in 720p, I'm very happy with Doug Drexler's explanation about his time on BSG where they discovered that 1080p effects look too sharp, even in comparison to higher-res film footage (quoted at Trekcore here
). I expect the balance will be correct on the Blu-rays, especially since the episode masters were posted on 1080p/24 D5 tape (thanks Maxwell Everett in the TNG Season 2 thread).
However, I wonder what the impact will be on composited shots - the Xindi council springs to mind. Does anyone know if the only the effects layer is rendered at 720p and then added to the 35mm or 1080p digital shot (the latter in the case of season 4)? Or would the entire shot be at 720p quality?
It would be a shame if Enterprise suffered a similar fate to the Babylon 5 DVD releases, although obviously at these resolutions and with no cropping issues, this could never look remotely as bad as that.