Cleaning leather seats

I've just bought a 2010 with Misty Grey (I think) leather interior. The leather on the seats has a brownish tint to it which I assume wasn't there when it was from the factory.

I've tried Turtle Wax Luxe Leather, which didn't really help. It removed the scuffs and made it smell a lot better, but other than that it still looks the same.

Is there anything I can use to make it look fresh and new? I'll post some pictures a bit later.