Lackey has said retirement is on his mind, rather than play for 500K. But I suppose that was just the rum speaking, he is doing quite well and is going to want a new deal. I think they should start by giving him a 1 year extension, paying him the money Dempster left on the table.
He also holds great value via trade. I think he will play it out and get a last payday. If Atlanta gave Derek Lowe $60M in the 2008 off-season, Lackey should have no trouble finding someone to pay him.