No, GSX was always supposed to be a separate product, to be released before the end of the year. After its release, it will work with all our sceneries for free (it will replace ParkMe) you'll just have to download it, and will work on all FSDT products without any registration.
By purchasing it, you'll be able to use it all FSX airports, default or 3rd party.
However, KLAX has been already made taking into account it will get GSX in the future...