When shopping for parts, there are three general strategies: budget, best bang/buck, luxury. The first and last of these is easy to describe, you either price optimize with minimal attention to performance, or “performance” optimize with minimal attention to price.
The middle approach is more complex however. The main difficulty is coming up with a metric to judge bang for the buck. For example, with hard drives, price per unit of storage space ($/GB) seems reasonable, or for CPU’s price per some measure of performance. You also have to make sure you compare reasonably similar items, i.e. you can’t compare 7200rpm vs 10000rpm drives.
What do you do for a display though? Displays have numerous measurable parameters, size, pixels, brightness, contrast ratio, response time, but there isn’t really a clear price-performance evaluation formula.
In the display world, there seem to be three general categories of prices. Cheap displays, high end consumer displays, and very expensive ‘professional’ displays. In the last category are things like NEC’s graphics monitors, or the Eizo ColorEdge line, easily 2x to 3x of high end consumer monitors. These displays not only compete along the dimensions that I mentioned above, they also boast wide color gamuts and fine grained image controls.
If I look back, I find that I tend to purchase things that are in the middle category of the three (price-wise). I remember buying: a 15 inch sony Trinitron CRT ($250), a 19 inch ADI CRT $(500), a 15inch samsung Syncmaster 531 LCD ($ I don’t remember, but a lot), a Samsung 170MP 17inch w/ TV Tuner LCD ($1700), and a Planar 20 inch PL201M ($950). This is over the last 10 years, mind you.
Not all the purchases were what I would call successes. The 19 inch ADI was a good deal for such a size (it was one of the first 19 inchers) but it had a funny defect where the screen would twitch once in a while, as if it were discharging something. The 15inch Samsung was one of the earliest LCD’s, and while was cool for the time, I was probably better off with a CRT that could do higher res. The 170MP was a luxury purchase, and it was ok. I used the TV functionality quite a bit, but the quality of the screen could have been better. The Planar, which I still use, I’ve been pretty happy with. But it seems a bit pricey when compared to these modern Dell’s that go for $400 (Though I did buy it in 2003, and it was a pretty good deal)
Anyways, if you couldn’t tell already, I’m looking at buying a new monitor, and I’m trying to understand the cost/performance tradeoff. The current situation is as follows:

• There are several 20/21inch 1600×1200 consumer models around $400
• There are several 20/21inch 1600×1200 ‘pro’ models around $1200
• There’s the Dell 2407 24 inch 1920×1200 for around $700
• There’s the samsung 244t 24 inch 1920×1200 for around $850
• There are several 24 inch widescreen ‘pro’ models around $1700
• Dell 30 inch 2560×1600 $1710
• Apple 30 inch 2560×1600 $2000
• There are super pro models of every size for 3000+

The Dell 2407 is definitely out, since people seem to have lots of problems with them (power supply whine, banding issues, and tinting issues) But how to compare the rest? It seems apparent that the ‘pro’ color-ness of it adds about $700+ to the price, and sometimes way more.
Here’s a couple stabs at comparing the 20 inch to the samsung and dells.

Interestingly, you can conclude from this that while the 24 inch widescreen form factor is a middle of the road in terms of price per physical display size, it’s not much cheaper per pixel than the 30 inch.
I think I care about number of pixels and color more than display size, so the Samsung doesn’t seem like a wise choice.