It also has it where it counts: depth. Almost everything I work on is helped by better depth: writing, coding, browsing. After a while, even the 1600 pixels of the 30" seem shallow. The iMac sure is wide, but it only has 1440 pixels in depth.
I know why they're doing it -- 16:9 widescreen panels are cheaper because of the demand for TV panels (it's almost impossible to get 4:3 panels these days) -- but I think it's a pity.
I seriously doubt that 16:9 panels would be cheaper because of TVs. First of all, TVs are usually somewhat larger. Secondly TVs have a lot worse resolution. Because of these factors, I don't believe that manufacturing panels for TVs affects the manufacture of computer display panels directly.
On a unrelated note, most people refer the other dimension as height, not depth.
Neither of those factors play a role: there are plenty of 27" televisions, and it's not the resolution that matters, it's cutting the glass. The official Lenovo blog talks more about this: http://lenovoblogs.com/insidethebox/?p=220
Apols for the depth thing, don't know where that came from. Possibly reading about bit-depth, another traditional area of Apple cost-cutting.
Actually, if you read the Lenovo post, TVs are precisely why the 16:9 ratio is being pushed by screen manufacturers: there's more TVs made (at 16:9), therefore, if they maintain the same aspect ratio for all screens they manufacture, there's less waste in the glass cutting process, which means 16:9 screens will be cheaper than custom-ratio screens like 16:10..
Not that absolute screen surface area is the most important metric.