I think it's realistic to say that a new Trek show would be facing a very different TV landscape than even when ENT left the air. Because shows do, as Roysten says, get less of a chance to survive on network TV than they used to (given it's general ratings I'm amazed that 'Fringe' made it to 4 seasons on Fox) and that means you have to grab attention from the start and then keep it.
Ironically, pay cable seems to allow shows more time to survive with lesser ratings but I don't see that being an avenue for a Trek series unless CBS gives Trek up to one. Plus cable seems to offer broader scope for content.
'If the Apocalypse starts, beep me!' - Buffy Summers
'The sky's the limit.....' Jean-Luc Picard, 'All Good Things'
courtesy of Saquist