According to FO, it would be: '13 SF.. '05 SEA.............................................. '08 AZ.
With all due respect to the 2005 team, it was a bit of an outlier season. They had 13 wins that season which really sticks out during a Seahawks era that never saw more than 10 wins in any other Holmgren season.
AZ went 9-7 the year they went to the SB, they were terrible for years before that season, and they were terrible again just two years later. They played inspired football in the playoffs, but it was clearly a fluke run.
SF should have gone to the SB the year before they went, and they have a very strong core that figures to compete for championships for many years to come.