I'd love to say what I know about upcoming episodes but obviously that wouldn't be a good idea.
The one thing I have yet to find out anything on is whether or not Heller is dirty.
This is something one of TPTB on "24" said about Season 5.
In Season One Jack Saved a President.
In Season Two Jack Saved a City.
In Season Three He Saved Millions.
In Season Four He Saved his Country.
In Season Five, He Will Save...