nope
He's averaging 9 points, 7.2 rebounds and 1.2 blocks in 23 minutes with 57% shooting.
He just turned 21... hasn't been fully healthy. It takes players a lot of time to return to proper form after microfracture surgery. A lot of his supposed potential was based on his explosiveness, lift and athleticism. Instead he gained too much upper body strength/weight and is trying to adjust to his new body, adjust to the NBA game after only playing a handful of College games, adjust to returning to basketball after being injured for a year... etc.
Dwight Howard as a rookie: 12 points, 10 rebounds, 1.7 blocks in 33 minutes with 52% shooting
Al Jefferson as a rookie: 6.7 points, 4.4 rebounds, .8 blocks in 15 minutes on 53% shooting
Too soon to call him a bust. That's silly.