Kavis wonders if he's the only person who wants 40 man raids back. I'm sure he's not the only person, but I'd bet he's in the minority. Forty man raids may sound super fun in theory, but in practice they are pretty miserable-- it's hell to coordinate the schedules of 40 people on a regular basis, and then it's even worse to actually get them to line up on time and do what needs to be done. I don't know if Kavis ever actually ran Molten Core or BWL or Naxx, but while 40 man raids were fun while they lasted, 10 and 25 man raids are much, much easier on raidleaders and guildies alike.
As Bornakk says, the devs love 25 man raids too-- since 40 man raids could be carried by about 25 good players anyway, it makes things much easier for everyone, in terms of individual contributions.
Now, if Kavis is asking to return to the 40 man content, I'm completely down with that. BWL, AQ, and Naxx were fun to go through when you had a good group rolling (as rare as that was), and the content there shouldn't be abandoned (Naxx, we already know, is likely being repurposed in WotLK). But as for a return to the days of trying to get 40 people together for five hours on a Sunday evening? No thanks.