It's on their minds from last I talked to some of the gang at DP9 at the Games Summit, and Cangames 2011 here in Ottawa. But their focus currently is on Blitz. For the time being they are somewhat supporting 2nd ed HG in their Gear Up free magazine pdf as they release stats for the RPG side of things, as the story progresses.
Actual development, from the elusive responses I've gotten when broaching the subject, prognosticate a hopeful release late 2012, or sometime in 2013 for 4th ed HG. Or, basically, when it's done, it'll get released.
I so much wish it'd be sooner, as I prefer the RPG over the miniature gameplay, but that is their focus right now, to rebuild their brand.