Even tho he's a "different" Spock, they've already played the Spock-Dies card. I think he's safe, ditto for Kirk, they will both do all three movies.
If anyone among the regular cast should worry, it's Uhura. Wouldn't be at all surprised to see her die in this upcoming movie. If McCoy gets more development in the next movie than he did in the last, he's also in danger for #3, although that's more of a long shot. Right now, he's too peripheral to bother killing.
Ideally, CBS will pick a few of the cast who are willing to do TV for a live action series to launch a few months after the third movie. That means Spock and Sulu, maybe McCoy, the others are unlikely. They might just need one to provide the PR boost for a show starring an all new cast of characters.