Joseph's team option will be picked up.
He's making $2M next year. He's not an injury waiting to happen (Mahinmi) or an injury waiting to be cleared to play (Oden).
The dude asked to go to the D-League to get some playing time. He's looking to get better. Maybe a trip to the Finals helps. His defense is adequate, and he's on a rookie contract. Did I mention that he's only going to make $2M next year?
Just because a guy's on a cheap rookie contract and hasn't immediately cracked the rotation on a team that made the Finals doesn't mean he sucks.
It means the team will pick up the option.
edit: and by 'next year', I mean the team option year. '14-'15.