I don't think there's really much in the US left to develop (that would result in a high volume of sales, that's where the key is - unless it would be developed purely out of personal preference/need and then sold on the side).
FSD have taken ORD and set their sights on JFK and DFW. It'll be fun to watch the s*storm of support problems that JFK will attract given FS9's (and I suppose FSX's as well?) less than stellar performance in the area. Although, admittedly, ORD is behaving nicely, even with MDW not that far away. Alas, this isn't about the performance of FSD's sceneries...
So, at at end of the day, we come to the issue of economics...sure, it's great to make small (or mid-size) boutique airports, but as far as the US mainland is concerned, I think all the potential motherloads have already been struck and all the bases are pretty much covered (especially with Imaginesim "taking out" some long overdue airports as well).
Sure, someone could revisit PHX or LAS, but the old Simflyers offerings are still holding up ok. They're obviously not anywhere near the quality of flytampa or FSD, but they don't look excessively dated yet either. I suppose there would be some potential for PHL, but personally I would not fly there, unless it was an absolute beauty of a scenery (like PVD, which I visit from time to time even though I rarely have any virtual business there).
As much as we'd all love to have our favourite airports modeled in FS9 or FSX (I've been waiting for a payware rendition of my home of EPWA since, like, forever, but everyone always forgets about Poland
), there's only really a small selection of those that have the potential of recouping development costs and making a few bucks for the devs (I'm looking at you LAX, FRA and LHR, how many times have those three been remade?).
I'm pretty sure Martin and George have to find the right balance between what is still left on the American domestic pie and what makes financial sense to commit a better part of a year's worth of life to. And, like I've already hopefully said, there's really not that much of that pie left.
Having spewed all that drivel, I'll still buy whatever they dish out as long as one major airline flies there (since I primarily fly heavy metal). Flytampa's sceneries are famous for their immaculate attention to detail and incredible performance, I'll gladly spend my money on it
