Although I use FS9 rather than FSX (mainly because its like GTR Evo is to LFS)... I will hope some third party company takes over the production of a new version.
I was quiet a flightsim nerd before I started to play "real" games, first own pc game was the FS2000 (which was brandnew back then) but I stopped playing it when the FS2004 came out, but i still have my 11GB FS2002 install on this harddrive.
Quiet sad that they stopped developing now, but i think its a good thing, afaik the FSX still uses the same base engine they developed for the FS2000, every version after it got slower and crammed with more "features".
FS2004 does the trick for me, and new scenery/planes/textures will still be unofficially released. No loss really, just means the online systems don't have to try and cater for new versions
Good riddance, it will hopefully "open the market" for some real advances. MSFS has had the same incredibly crappy flight dynamics for at least 10 years now.
Flight Simulator certainly isn't great, but its the only thing of its kind that leats you flight the entire world in detail with 1000s of addons. Xplane doesnt come close enough right now.
Hopefully something new will pop up, looks like its time to buy FSX while copies last then.
But in a way I'm glad, because I spent a couple of years downloading stuff for FS2002, then the whole community moved on to FS2004, so I had to buy that to keep up, and now everyones moving on to FSX, hopefully FSX will end up being developed into something much greater because people wont be moving on when a new version comes out a few years later, rather like GPL, GPL never had a sucessor and so it developed from a flawed game with poor graphics into what it is now, 10 years on.