Simaddict, I hope you're right, and that somebody is paying attention.
Austin and MV, let me make two points. First, Flight Simulator has been open for third party development--aircraft, scenery, add-on and companion programs, etc.--since before Microsoft bought it from BAO. BAO had a small staff and used its resources for development of the base program. Third parties added aircraft and later, scenery. Microsoft (in one of its few rational acts) continued the policy.
Second, programs (even sims like FS and SS) are not normally updated more than once a year, except to fix bugs. They are a moving target to some extent, but the interfaces must remain relatively stable or their own ships, aircraft, scenery, etc. would have to be revised for each release--and that's not practical for anybody.
It is eminently practical for VSTEP to open the interface, and there would be many long term benefits to VSTEP as well as to the users. I hope they'll do it!
Barnacle