Every rumor I'd heard about WOTC doing a new version of d20 Modern was before the economic crash, and the multi-round layoffs.
Given that, and given the fact that d20 Modern was considered a "niche-level success" by WOTC's standards, I would seriously doubt that there are current plans to revive it.
...which is the main reason that I've gone ahead and decided to proceed with Adamant's Odyssey System project, where we will be releasing our stripped-down d20 rules set in a free alpha, 100% Open for gamers and publisher's use.
Given that, and given the fact that d20 Modern was considered a "niche-level success" by WOTC's standards, I would seriously doubt that there are current plans to revive it.
...which is the main reason that I've gone ahead and decided to proceed with Adamant's Odyssey System project, where we will be releasing our stripped-down d20 rules set in a free alpha, 100% Open for gamers and publisher's use.