The incompetence of Interplay suits killed FO3. Would things have been any different if they'd never pursued a console rendition of the franchise? Interplay has squandered its intellectual property, and they'll probably sit on it like Electronic Arts did Wasteland, forcing someone to use their noggin and create their own post-apocalyptic mythos.
Van Buren looked like a great engine, and I deeply regret it never seeing the light of day, but there are other engines, and other quality storytellers out there. I stick by my original poll answer-- losing a few of the designer superstars doesn't doom what we love, which is the post-apocalyptic genre.
That's what this site is about-- the PA genre of CRPG. It is NOT about Fallout, because Fallout belongs to Interplay, not the fans. If you say it's about Fallout, then STFU and swallow Brotherhood of Steel, fanboy.
The original Fallout was a masterpiece, but the franchise has been in decline since then.
Wasteland came first. EA let it gather dust. Fallout came in tribute. The next big PA game will come as a tribute to its predecessors-- not a remake, not a sequel, but a title worthy of the best of the genre.