There are so many regular sales all over the place, that the scheduled sales have nearly lost all appeal.
This - heck I mostly don't even bother checking the steam sale page anymore as its often a good 30 odd games listed nearly every day! I just poke around my wishlist every so often or look at the first page only of discounts.
Gamers are being hit hard with mass sales - sadly it seems to be the current leading theory that you can't have too many sales. On the one hand its nice we get cheaper stuff; on the other hand its kind of pushing us more toward a market who are more willing to wait for stuff to hit sale prices because unless your AAA top rated you'll be on sale before you know it (and heck the indy scene do this badly, some of them jump onto bundle sales before they've even been out for months it seems!)
That said I've never understood why Steam always does their Autumn sale so darned late and so close to Christmas! Though I guess it is one last good attempt at personal purchases before everyone gets hammered in the wallet in christmas.