They've been saying since 2008 that they will not be using time travel again in the forseable future.
If production is meant to start around January (as Quinto has indicated in a couple of interviews) then at least some of the 'rumours' should start to have a basis in fact I'd have thought.
'If the Apocalypse starts, beep me!' - Buffy Summers
'The sky's the limit.....' Jean-Luc Picard, 'All Good Things'
courtesy of Saquist