I think Hasbro's stance up to now is that they don't want to do headmasters again, as if you lose the head then you just have a headless toy. With targetmasters like scoop, if you lose the targetmasters you still have the figure.
On top of that, IDW's Brainstorm isn't a headmaster, so I'd say the chances aren't *that* good. Having said that, I would flip the hell out if they did, I love the headmaster gimick
I have Smart Robin and I think he's awesome. Really sleek altmode and great looking bot mode. It has limited shoulder articulation, like the previous two in the line, and as previously stated the face has a face rather than a faceplate. It's not an issue for me but I know it is for some people