I think this is the right move. Tomlinson is the only back on the roster with experience as a pass protector. If getting to the Super Bowl means getting past teams with Dwight Freeney and James Harrison, having a back who can help out is important.
I am hoping the Powell pick means the team is going to get serious about reducing Tomlinson's workload. LT showed he still has some moves in 2010 but will wear down if he has to work to much as he gets older. An almost exclusive third down role where he could use those blocking and receiving skills would almost be perfect.