According to Reds.com, David Weathers, Royce Clayton, and Jason Johnson are the first three players to file for free agency this off-season. The article goes on to say that Weathers may or may not be back, Clayton and Johnson probably won't.

Meanwhile, John Hickey of the Seattle Post-Intelligencer says that Johnson could be in the plans for the Mariners.

Seattle has had three consecutive last-place finishes, and if things are going to change, general manager Bill Bavasi and his crew see the need for an influx of starting pitching.
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The market for quality starting pitching in free agency is relatively thin. The Mariners have interest in, among others, Jason Schmidt, Jason Johnson, Jeff Suppan and Adam Eaton, plus maybe Miguel Batista, Mark Buehrle or Ted Lilly.

Thin, indeed. Though Johnson was 0-0 with a 3.12 ERA for the Reds, I don't remember him being that good. Could be a tough season for acquisitions.