This is about as mean as the usually-circumspect Neal Huntington ever gets:
"Sitting here today, we feel like we have one Major League third baseman, and that is Andy LaRoche," general manager Neal Huntington said. "[Walker] needs to continue to mature and get stronger. He still hasn't really dominated the Triple-A level to show that, 'Hey, I'm ready to be a Major League player.' He hasn't necessarily earned his way to the Major League level."
I mostly agree, of course. I think it's interesting, though, that both Huntington and John Russell say that Walker needs to get stronger. Other than his defense at third base, Walker's power is the one aspect of his game that has clearly developed well since he was drafted in 2004. His isolated slugging averages have been very good the past couple of years. He's also shown a good arm. If the references to Walker's strength don't have to do with his power or his arm, then I'm not sure what Huntington and Russell are talking about.
The real problems with Walker are that he doesn't hit for enough average, and he doesn't draw enough walks. He's had exactly one OBP above .345 in any year since he was drafted, which is terrible for a former first round pick. Walker hit .194 in a very small sample in the majors last year; while that shouldn't really be held against him at this point, an extremely low average would be a very likely outcome if he were allowed to play much in the bigs next year.
There is reason for some hope, though--Walker hit well down the stretch at Indianapolis last year, and he kept hitting in Venezuela this fall, posting a .267/.370/.448 line in 116 at bats there. The average is still too low, but he did draw a bunch of walks for the first time since 2007, when he was with Altoona. A line like that at Indianapolis might convince me that Walker is ready to help the Bucs, at least in a bench role.