Heavenly Sword.
Rogue Galaxy (I agree!)
Timesplitters: Future Perfect.
Battalion Wars 2.
Terracon.
All games which I really enjoyed, had a great premise and showed great promise yet sequels seem extremely unlikely. I guess we may see new Timesplitters, Heavenly Sword & Battalion Wars far in the future but as more time passes they feel like they're slipping further away.
edit: Oh yeah and Star Wars Battlefront 3. I forgot about that one!