I foresee two 'events' with regards to the 733. Event 1 is "port to XP12 'as is'. Event 2 is 'upgrades beyond the port'. The goal of event 1 is to get it to work in XP12 the way it does in XP11 given XPlane changes. Those who have made 733 purchases since early this year will certainly get the XP12 port version for free as stated on the XA product page. Beyond that XP12 port though, we have not made any determinations about what may or may not constitute a 'paid upgrade' beyond the fact that it shouldn't be egregious or outlandish. Regarding features 'beyond the xp12 port'... we have and hear arugments all the time for/against variants, cargo versions, etc and have not made up our minds yet about what may be next. The obvious things todo are the FMS work and upgrading all the 3D/textures/animations.
As far as MSFS, a lot of us developers have kept an eye out on the whole market/dev process and a port is not a trivial thing, regardless of what Fenix / inisim is doing. We're talking multiple 1000s of man hours easily, and at my age and road traveled, that's a tall order.....regardless of the money potential. I rather enjoy my little world in X-Plane and those users who also see the same value in it. Perhaps Fenix, iniSim or someone else can do a 737-300.
I can't speak for any other devs in the X-Aviation ecosystem, but for our part, we'll probably stick to X-plane with the 733...best I can tell from today.
-TomK