It took him some time to get adjusted, but in the 10 starts prior to his getting bumped from the rotation, he'd delivered seven quality starts. His peripherals are solid if unspectacular, and his 4.24 FIP is actually well above-average when it comes to back-end starters. He gets talked about sometimes as something of a salary burden, but frankly, his three-year/$23 million deal looks like a bargain given his performance this season.
Given the Braves' current excess of starting pitching, the decision to move him to relief is defensible, but in the long term, I'm not sure the bullpen is where Kawakami belongs. He's faced some fatigue issues after the 75-pitch mark (1.062 OPSa), but up to that point he's been quite effective (.773 OPSa pitches 1-25, .700 OPSa pitches 25-50, .585 OPSa pitches 50-75). Part of those fatigue issues probably have to do with getting used to taking turns on one less day of rest (since Japanese clubs generally use six-man rotations), but even if he still runs into a wall late in games, he's more valuable as a starter you hook quickly than as a seldom-used mop-up long reliever. There's some merit to the idea that Bobby Cox devised during the Mets' series, where he used Kawakami to record a four-inning save, but that seems a bit too avant-garde to have Bobby do that on anything resembling a regular basis.
I'm not sure he's flashy enough to garner much if any real trade value, so I think you keep him around for 2010, and slide him back into your #5 slot and enjoy the reliability of the NL's best fifth starter.
The bottom line: With all the pitching talent on the Braves' roster, it's not hard to forget about Kawakami, but let's not underestimate the value of a guy that can take the ball every fifth day and give you quality starts.