Rockstar have just announced that the official GTAV trailer, yes, the official one, will be coming this Thursday. We can safely assume this trailer will be the final one, the one which shows off the game in its completed form (as opposed to the previous ones being made during development). It's quite likely the one to be used on TV as well.
Rockstar haven't set a release time yet. We're going to go ahead and guess 10AM-12PM EST (3PM - 5PM GMT) as it normally is, but do keep checking back, we'll hopefully get an exact time confirmed soon.