I know that Ultimate Traffic will work by copying the bgl file over from fs2004...however, can the program be installed into FSX right now or does the bgl file have to be copied??

I seriously doubt it could be installed in FSX right now.For one thing the installer doesn't know what FSX is or how to find it on your computer.I'm sure the Flight1 team is working on how to move the product to FSX. They did a really good job with the move from FS2002 to FS2004.But it will take time.The big question will be adding parking in FSX. Because without sufficent parking - AI is a real FPS killer.With the cooperation which MS/ACES has shown with addon developer community with this releae - hopefully it will be less than it took last time.But we are all being foolish if we expect any of our current FS2004 addons to be fully FSX ready in less than three months after the official release of FSX.