Good question
It may simply be a simple supply and demand problem. The big guys like Dell (for notebooks) take all of the available panels. BTW there is more margin in notebooks than desktop monitors thus higher profits.
Also there's a distinct difference between the notebook and desktop monitor markets, and therefore between the panels designed for each. Desktop monitor panels tend to be brighter having better contrast ratios, faster pixel response times and viewing angles then those high resolution versions used in laptop displays.
Desktop monitors have been designed intentionally for lower resolution (pixels per inch), in order to make them more competitive with the desktop standard CRT monitor. Also most people who what higher pixel densities want larger sized monitors. If you look at the trend for LCD monitors the sizes and approximate dot pitches match (or are close) to those of the standard CRT.
Jim Witkowski
Chief Hardware Engineer
Cornerstone / Monitorsdirect.com
<A HREF="http://www.monitorsdirect.com" target="_new">MonitorsDirect.com</A>