Each player changes his new team's dynamics at his position. A quick look at the immediate implications.
Position affected: cornerback
Implications: Greg Toler no longer projects as the starter opposite Dominique Rodgers-Cromartie. Teams use more than two cornerbacks a significant percentage of the time, so Toler figures to get on the field anyway. But there's no question Toler will see fewer snaps now that Peterson and Rodgers-Cromartie are the top two corners. Speaking of Rodgers-Cromartie, he's also affected by Peterson's arrival. His status as the most talented cornerback on the roster is in question. Peterson could raise overall expectations for the position.
Position affected: outside linebacker
Implications: The 49ers expect the versatile Smith to help out in more than one place, but outside linebacker is his primary position. Smith's arrival could signal Manny Lawson's departure via free agency. Lawson, a first-round choice in 2006, has been solid, but not a standout (except on special teams, where he can be a dominant force). Lawson, like Aaron Curry in Seattle and Levi Brown in Arizona, gets measured in relation to his draft status. Each was arguably over-drafted, but that doesn't make any of them bad players. Smith's addition does call into question whether Lawson will return.
Position affected: defensive end
Implications: Quinn projects as the eventual replacement for right defensive end James Hall. I don't see Quinn's addition endangering Hall in the immediate term. Hall showed last season he's still a productive player. He's a respected leader and much stronger against the run than Quinn would be at this stage. For now, Quinn gives the Rams another weapon for rushing the passer. He makes their rotation deeper. For the long term, he gives them a replacement for the 34-year-old Hall, but there's no rush. Hall can mentor Quinn, who did not play in 2010 and needs some seasoning.
Position affected: right tackle
Implications: Carpenter projects as the immediate starter at right tackle. Sean Locklear has been Seattle's starter previously, but the team shortened his contract to run through 2010 only. I wouldn't expect him back. Stacy Andrews was another candidate to start at right tackle, but with Carpenter in the picture and Andrews' salary spiking to $5.25 million in 2011, Andrews' future with the team appears in question. The Seahawks expect Carpenter, left tackle Russell Okung and center Max Unger to make Seattle tougher up front. Carpenter's addition signals a culture change on the line for Seattle. It could be "out with the old" at this position.