According to PC Gamer, the full game won't be available until 2016. What you get in December, for $60, is one-shot missions. Initially I reacted pretty negatively to this news, but hear creative director Christian Elverdam out:
What we’re thinking is you get nothing more than a portrait, so you can’t really find the guy on instinct or anything like that. You’ll have to work your way around the level, finding his routine. If you make him nervous and he escapes, he’s gone forever. And then when you finally figure out what you want to do, that kill you do is going to be the kill you can do. You need to really pay attention because you’re not going to get a do-over. We really believe that you’ll have a segment of players who race to be the first. There’ll be bragging rights, Twitch streams, discussions of different strategies.
Sounds pretty intense to me. As long as the target A.I. doesn't get easily spooked or you can easily fail a mission through no fault of your own—as in previous games—I think I'm going to have a good time with early access Hitman 2015. Naturally I'll stay away if early word-of-mouth is severely negative (although I'm glad I checked out Absolution for myself), but I'll probably wait to pick this up until I'm finished with Fallout 4... which, in turn, I won't be picking up until I'm done with Witcher 3. And, at this point, I'm wondering if Witcher 3 actually ends.