CBS is the SOLE owner of Star Trek, Paramount, owned by Viacom, (a now separate company after the 2006 split) has contracted licensing rights to make the films. The decision is CBS. That said, there are some legal ramifications that need to be sorted out before CBS would 'sign off' on this, such as worker time compensation (for the film restoration) and possible union issues among many things. Not saying it could not happen, just a lot of red tape for CBS to deal with.
@Christopher, are you sure Paramount still has the joint copyright license on books, etc.. I thought that had recently changed to all CBS. You would know better obviously since you deal with them more. I may be wrong.