Forget his brother, look at him on his own merits. He's clearly a good player.
Okay, he's had an average 18 months. How much of that is an irreversible decline, how much of that is the aftermath of malaria, how much of that was due to playing alongside the walking disaster that is Gallas? My god, I will never forget Gallas's first ten minutes vs the rags when they got tonked. The most complacent, arrogant, down right stupid display I can ever remember seeing from a top flight defender.
Apparently Touré has been isolated at arsenal, along with Adebayor and Eboue. Maybe a return here would see the old Toure return? Even at his current level, he's better than Richards and Dunne, but not so long ago this lad was amongst the top 4 defenders in the league. Very pacy, very powerful, very comfortable on the ball, and always where he was needed. It's got to be worth a shot. Plus, he can do a very good job at right back when needed.