To add a bit more to what I wrote, I'll defend the developers about how little they changed from TFC to FF:
I like to think of Hockey. How long has Hockey been around, with the same type of people loving to play it, and loving to watch it? Of course it's been tweaked and patched since it's conception (maybe in the 1800s? check
Wikipedia,) but it's still the same game, and people still love it.
While it's true that people crave change in many different things (like music,)
games in general (be they PC games or athletic games) merit an exception from change, just by their nature (in regard to psychology.) Just like Hockey, Fortress has no reason to change; it's a great game already.
The developers of Fortress Forever took the conservative approach to remaking a great game, and I respect them for that.
-Joker