Oh, on the contrary, it's clear already from the publicity material that Into Darkness, like its predecessor, is focusing on Kirk, Spock, and Uhura as the three leads. Not only is it natural that they'd want to make the female lead more prominent in a modern film series than she was in the '60s, but there's also the fact that Zoe Saldana is a considerably bigger star and bigger box-office draw than Karl Urban -- indeed, she's arguably the most famous member of the regular cast. They'd be fools not to keep her front and center.
More famous than the (now) King of Gondor??? I think not!