There are so many bands from that time period of say 03 to 07 that kind of just disappeared. I'm actually surprised Arcade Fire came out alive after a few stinker albums they put out.
Which ones were stinkers? Not everyone can/wants to put out Ten/Funeral every album.
I'd consider Neon Bible a stinker... and while Funeral may have been perfect in 04', over time I feel it has lost its luster. So... putting out one stinker, plus Funeral maybe not being as awesome as it once was in a course of six to seven years is an easy recipe for a band to disappear. Obviously, that didn't happen...
Edit: And what az just said....