Yes, an obsession without basis. There's no logical reason for making the iMac any thinner. Also, we need at least one computer with an optical drive.
Hear, hear!! Actually, thinner makes a lot of sense for iPads, Airs, and MBPs as it serves a very useful function in terms of portability and in-hand uses. But once we got the current LCD iMac forms, the AIO has dramatically reduced the desktop footprint. You could reduce the footprint a bit more by reengineering the support pad, but without that, making the main compartment thinner wouldn't help at all.
If the compromises made on the retinal MBP and air are any guide, you have to give up some function to get the advantages of thinness for portable models. These include dropping the optical drive as well as the ability for users or ordinary local Computer shops to repair or upgrade RAM and drives (to say nothing of batteries, which aren't relevant to desktops). For me, an extra half inch off of an iMac just isn't' worth going to an AIO that removes the optical drive (and a desktop optical add on
increases the total footprint) and makes simple RAM or SSD upgrades/repairs something that involves living near an apple store or mailing it away.
A half inch thinner doesn't do all that much for footprint. I don't think hanging it on a wall (one reason for thin and flat) is likely to be as a popular option, as you can't adjust viewing height, distance, or angles for various users. So the main reason for thin on a desktop, unlike portables, is aesthetic. Give me at least the same or better function over minor aesthetic changes. If Apple can make a thinner iMac that maintains the optical drive (I'll need at least one for the foreseeable future) and continues user replaceable RAM and drives, I'm all for it. But don't take away function just to make it prettier.
