Like Alan Wright the 30 year old has put pen to paper on a two and half year deal, taking him to summer 2006.
Shaw told Blades World; I'm very pleased it's done - I'm excited about joining such a big club."
He will take over Michael Brown's number 7 shirt which may make Blades fans feel aggrieved. Shaw will probably make his debut his Saturday when United face West Ham United at Bramall Lane in front of Live Sky TV (kick-off: 5:35pm).
However, he wont be able to play in the following game when the Blades travel to Nottingham Forest in fourth round of the FA Cup. Shaw is cup-tied as he played and scored in their 3-2 win over Charlton Athletic in his last game for the Gills.