Hitamn 5 is rumored to be announced at this year's E3. While an official confirmation is more than likely, it will probably not be called Hitman 5. Square Enix has just filed a trademark for Hitman: Absolution. Hitman is a series that follows Agent 47, an assassin-for-hire with his fair share of emotional baggage.
If another Hitman game is announced, what do you want to see happen with the series? The title Absolution suggests 47 wants forgiveness. I'm guessing he's commuted his fair share of "sins."