Aerosoft NIght Environment Israel announcement

both platforms are good
there is an advantage at the moment to XP with his 64bit support
but FSX/P3D is much more popular and user friendly
and is sure to catch up shortly with XP

the new P3D development is in full swing
LM and P3D already released 64bit SDK for developers to start working on

with that said the current FSX is the most used platform
with unparalleled scenery and models developed for it
the reason most people are waiting for P3D
is because it’s a natural move to P3D
once the platform is fully stable
it’s as if your upgrading from windows 7 to 8
with backward compatibility support to FSX scenery and models