You're right, Zeller does move well.
Rondo will probably make him a 16 point, 10 rebound player per 36 minutes. (he's not too far off that now).
I'm assuming they'll try and pump up his value to the max. He's come at the perfect time after 2 seasons and a bit of time already starting for the Cavs.
Hopefully he becomes a valuable trade asset to send out for an All Star one day, in the mean time it should be real fun watching him play with a passing guard like Rondo.