I am also a loyal customer and I would love to have this scenery for FS5.1. 
What!!!! The new KLAX will be for FSX and possibly FS9.....Besides its been along time since that version has been out and past.
Your sarcasm detector must be out of order.
It cracks me up about how mad people get when a scenery is not going to come out for their old FS. LAX may be outdated for Cloud 9 but poor KSLC, CYVR , KBWI and so forth never to see a single payware company touch them, instead interest only in redoing outdated work. I have FSX and FS9 on my rig probably never to be touched again but with $500. dollars probably invested. Stop buying FS addons and save for a new rig! lets all move to fsx change is good and gets only better, imagine the day when flight comes out and FS9 will be gone just as fast as a default concorde! 
You never got this mad when your cassette tapes or VHS collection moved to Discs did you?
I think speaking for Microsoft Flight is a bit too much as only some developers have been told/shown what's up with that and all are under NDA so lips are sealed. It's not even the same development team I understand. So other then a few videos and pictures it's hard to tell if third party developers will move in that direction or want too. For all we know it might be geared for a larger audience witch might hurt those who strive for realism as aviation realism is a small niche community. It's might even entail development techniques like tessellation, etc witch would be new to FS developers I would say. That might be going too far on my behalf but to say what devs can do or cannot do; but saying Flight will replace something when we don't even know what Flight is is going to replace is maybe going to far on your behalf. I'd LOL if we saw a need to play and have to have Windows Live as that has arcade written all over it. They even tried to make FSX a bit arcade elements adding "missions"! What fun and realistic those were, but from a marketing aspect it might get a non hardcore simmer or first timer to buy the game.
Heck, if I was Microsoft I'd me kinda mad my 50 to 80 dollar "game" (depending on how you use it) have a economy of it's own where one airport can cost as much as the original game all of witch I don't see a dime.
