Well seeing how this as been brought back to life, I'm curious as to whether or not I should go and install this update?
Now mind you I have had no problems since I originally installed FS9 I have the basic lag here and there but nothing major, now is there any reason why I should or why I shouldn't give this update a try? I can always use a increase in FPS

My main concern is the fact that I have USA Extreme Landscapes installed which I really enjoy, does adding this update take any of that away? Reason I ask is that after reading the info at the MS site they say that 3rd party stuff may either take away from the update or vice versa.
Im also curious about multiplayer, can I fly online with someone who may still run Ver 9.0 even if I have Ver. 9.1?
Also what can I expect not to work after updating?
Will this update render add-ons or anything useless (basically should I just do a complete uninstall/reinstall) or can I apply this update and expect all my add-on aircraft, eye candy tweaks, config tweaks etc to function as normal?
And last but not least what is the definitive process to install the patch with the least risk of problems?
Thanks in advance!