CBS Sports is reporting that Joseph Addai and Charlie Johnson were given tenders for the 2011 season. These moves are not 'official,' which is a fancy way of saying the Colts have not announced the moves. The likely reason they haven't announced them is because in one week they could be moot. There is currently no Collective Bargaining Agreement for next season.
Thus, tendering players for 2011 is essentially meaningless.
Both Joseph Addai and Charlie Johnson are listed as unrestricted free agents in 2011. If a new CBA is signed this week and one of the stipulations of that CBA is players listed as UFAs for 2011 are given the chance to hit the open market, then all these 'tenders' mean nothing and the Colts will receive no compensation for any other team that signs someone like Addai or C.J.
So, to make things simple, it's very possible both Johnson and Addai will not be Colts in 2011. We just don't know until a new CBA is signed.