It is being made and to deny that fact is to be delusional. I am not saying that Bethesda are incapable of making a good Fallout game, but I am saying that it is highly unlikely they will choose to. I am expecting Bethesda to make out of Fallout 3 is a game similar in style to their past games such as the TES series, PotC, and the such. If they do what I expect then the game will be Fallout in name only and I have yet spent money on a game that is like that.
If you are going to name a game off a older title then have it be as close as possible to that title, otherwise don't use the name at all.