The issue here is that 1920x1200 with proper scaling would give you black bars for 1080p HD content anyway, and therefore you might be getting a 23" image displayed onscreen rather than a true 16:9 24" image. This monitor fills an important gap in the market. There will always be a demand for higher-resolution screens for productivity purposes, but if your main computer use is HD gaming or native 16:9 video, then this is a big plus.
I agree in general.
The Dell s2409W is little closer to a cinema proportion.
If it has proper scaling, the movie image will be a touch of a bit larger than on standard 24" ---- and still with "black bars for 1080p HD content anyway".