The 2006 Indianapolis Colts
The 06 Colts compare favorably with the 1976 Oakland Raiders. The Raiders were a team that was always good--check out their regular season records from 1967 to 1977. They were actually in the AFC championship game 5 straight years (73-77), but until 76, they always came up short. Then in 1976 they were spectacular, going 13-1, overcoming the Steelers in the playoffs (they had met in the playoffs the previous four seasons, with the Steelers winning three of the games), and finally getting the validation of a Super Bowl victory. They are now thought of as one of the great teams of the 70s, though the Steelers are THE team of the 70s.
The Colts under Manning have had seven playoff appearances; all seven of those playoff seasons featured 10 win seasons and five of them were 12 win seasons. The Colts have been a spectacular regular season team that just always came up short. They've finally broken through. Given the way the team is built, one can question whether they will get through and win another one in this decade (though Manning always gives them a chance--he's that good). They probably won't be remembered as the team of the decade--that's the Patriots. But they broke through and they don't have to have the reputation as losers, as a team that was always losing in the playoffs.
The 2006 Chicago Bears
When looking at all the Super Bowl losers, it's hard to find a comparison for the Bears because we don't know what is going to become of the Bears. 5 of the first 6 Super Bowl losers went on to win a Super Bowl within 10 years. Will that be the Bears, and will this Super Bowl loss be remembered in history merely as a stepping stone? There are teams that made multiple Super Bowls but always lost--the Vikings (69, 73, 74, 76) and the Bills (90,91, 92, 93) most notably. And then there are the teams that lost one Super Bowl but were never closer to a championship than the year they lost (at least not with the same nucleus, like the 72 Redskins, the 80 Eagles, or the 94 Chargers). We don't know who to compare the Bears to. So much depends upon what they do at quarterback, because they've got the great defensive personnel and a great scouting front office that always finds more great defensive players to add.