Concerning VFR , I like flying on the west coast between San Francisco and San Diego (I once tried to drive that very same distance by car). 
Now, if you follow highways and freeways, there is still a lot to be done for the programmers. I'm not talking about the streets in photorealistic areas at major cities, they are ok. But the road 'textures' used in rural areas are so completely unrealistic. They are just lines floating above ground. Anyway, VFR flying in FS 2002 has improved dramatically in all areas of the world. Now danish school children can navigate easily in the simulator, because they already have learned every corner of their little country by heart. There are a lot of islands, peninsulas, inlets and bays with their own characteristic shapes. All of these details are correctly put into place in the simulator. Excellent.
Another brilliant feature is that intelligent ATC (Air Traffic Control) has now been introduced. I must say it works very impressive and convincing. May I add that ATC has been integrated in the Flight Unlimited simulator already for a long time, but of course only for a more restricted area (the U.S. West Coast).
Flying IFR is really amusing in Microsoft flight simulators, and always has been. Now a very good GPS system has been added, and it works nicely.
I tried to make a GPS real time flight from Copenhagen to San Francisco, but unfortunately the system crashed only 200 miles from SF. It seems that there might be an overflow problem in the GPS system somewhere. Then I tried a little shorter transatlantic flight from Copenhagen to Chicago without any problems. I find GPS fascinating but, to be honest, I prefer traditional IFR flying navigating on my own. It's really thrilling when you try to take a heavyjet down to the runway in almost zero visibility, after you might have been flying for hours. If you can't find the runway and maybe run out of fuel trying to - oh what a shame that would be. On the GPS picture I have just departed from Copenhagen Airport, runway 4L. Over the waters between Denmark and Sweden I switched on the GPS, and the aircraft turned left to catch up with the green line. In a few minutes the plane will bank to the right, to follow the exact Great Circle Line into Chicago. The distance is 3670 nm.