Speaking at last nights BFI, 11th Doctor Celebration Event, Steven Moffat confirmed that Series 8 of Doctor Who will not be split.
Back in October, Moffat also confirmed that there would be "at least 13 episodes" in Series 8, with no confirmation (as-yet) if it counts the 2014 Christmas Special.
There had previously been rumours that the series itself would consist of 12 episodes with the Christmas episode making up the thirteenth.
+ Series 8 of Doctor Who will air in August / Early September 2014.
[Sources: BBC; Tim Vine]