Here are several thoughts on the signing:
I like the signing for the simple fact that Pittsburgh needs Polamalu. The team -- and particularly the defense -- just isn't the same without him. The Steelers probably would have put the franchise tag on Polamalu and worked out a deal next year if it came down to it. But the Steelers and Polamalu should be happy not to have that hanging over them this season.
The extension shows the Steelers are confident in Polamalu's health. He's suffered two significant injuries to his knee and Achilles the past two seasons. Pittsburgh could've easily taken the wait-and-see approach in 2011. Instead, the Steelers invested in Polamalu through 2014. He is arguably the NFL's best defensive player when healthy.
From a team perspective, I continue to be amazed by the work of salary-cap specialist Omar Khan. The Steelers began the offseason about $10 million over the cap and worked out large extensions for LaMarr Woodley, Lawrence Timmons, Ike Taylor and Polamalu. Key players like quarterback Ben Roethlisberger and linebacker James Harrison restructuring their contracts certainly helped.
Continuity continues to be the key for Pittsburgh. The Steelers are keeping the team together in hopes that this core group can make another title run. Players like Hines Ward, Polamalu and Roethlisberger have been to three Super Bowls together (winning two). The team is getting older, but its window remains open.