It all depends how Millar's run ends. Suppose the Ultimates as we know them break free of S.H.I.E.L.D control and become the Ultimate Avengers. In that scenario, Fury would likely promote the Reserves to the primary team and possibly boost their ranks with characters like Falcon, Captain Marvel, and various other classic Avengers who haven't made an appearance in the UU yet.
If that were the case, it would be sooooo 'The Ultimates' to have S.H.I.E.L.D./the US Govt. and Steve Rogers/the Avengers get caught up in a public court case over who has the rights to the name and image of 'Captain America.' :lol: