BREAKING NEWS: Bucky and Natasha will be starring in the new Thunderbolts book that comes out in December.

Not exactly…but before I go into Bucky’s situation, I’ve got to take a moment to clarify Natasha’s situation, since this is a very common misperception: 

Natasha does not have the super serum. What she has are chemical enhancements that have stopped her from aging. The MU has employed numerous chemicals, formulas, and dodgy genetics to explain why certain characters don’t age and a lot people - and pros are just as guilty of this as the rest of us - tend to throw around “super serum” as a catch-all for all of these. But the super serum is something very specific to Steve Rogers and the Captain America mythos. Natasha’s chemical enhancements are very different from Steve’s serum, and very specific to Natasha’s history. For more on why this distinction is important, I really recommend these two posts from FYBW: [1] [2]

So back to Bucky. The situation you describe could have been their future before the events in Fear Itself. Before then, Bucky had no enhancements outside those needed to control the cybernetic arm. But after the battle against Sin in Fear Itself #3 that seemingly killed him, Bucky was given Nick Fury’s last dose of the Infinity Formula:

The Infinity Formula does end up saving Bucky’s life:

but it’s important to remember that no one knows the long-term effects it will have on him or his health:

She is talking about his death in Fear Itself #4.

It’s from the Young Allies Comics 70th Anniversary Special #1:

Unfortunately it’s a Rhodey situation. (¬､¬)

I haven’t seen the latest solicitations, but in an interview this week Spencer said that there are two Infinity tie-in issues and then issues 8-9 will go back to the A.I.M. Island stuff, so it really doesn’t sound like Bucky’s showing up anytime soon.