Actually, the reason I joined in on this thread was because earlier today I was curious about how much I could build the equivalent to a mac pro for so I went on to Newegg and found all the components of one and it came out to about $2000. If you don't believe me go try it for yourself. Not only that but for basically the same price (around $2000) you can actually build one with better specs ie. more ram, bigger HD, and much better graphics card.
$710.99 Intel Xeon E5440 Harpertown 2.83GHz LGA 771 80W Quad-Core Processor Model BX80574E5440A - Retail
$710.99 Intel Xeon E5440 Harpertown 2.83GHz LGA 771 80W Quad-Core Processor Model BX80574E5440A - Retail
$349.99 ASUS DSEB-DG Dual LGA 771 Intel 5400 SSI EEB 3.61 Server Motherboard - Retail (lowest price dual LGA711 with 800 MHz FB-DIMMs)
$33.49 Kingston 1GB 240-Pin DDR2 FB-DIMM DDR2 800 (PC2 6400) ECC Fully Buffered Server Memory Model KVR800D2D8F5/1G - Retail
$33.49 Kingston 1GB 240-Pin DDR2 FB-DIMM DDR2 800 (PC2 6400) ECC Fully Buffered Server Memory Model KVR800D2D8F5/1G - Retail
$50.00 Western Digital Caviar SE WD3200AAJS 320GB 7200 RPM SATA 3.0Gb/s Hard Drive - OEM
$69.99 KINGWIN ABT-730MM 730W ATX / BTX SLI Ready CrossFire Ready Active PFC Power Supply - Retail
$30 Graphics card
$50 Case
$20 Optical drive
$10 Mouse & Keyboard
Total: $2068.94
Okay, so you can put together a similar spec machine for close to $2000 (not including shipping, time to install and an operating system).
In my mind when you buy a "Pro" machine you should expect to get high end components, even if they are unnecessary.
I believe the components inside the Mac Pro (at least Mobo, Case, Heat Sinks and PSU) are of higher quality than those used to put together the above quote. So if you factor in another $200-$300 for this (not that you'll ever get a case as good as that of the Pro). Keep in mind that the Pro comes fully assembled with OS installed (important if you are getting lots of them).
When it all comes down to it, Apple released this system at this price over a year ago and today you can't really do too much better. I have to say that anything above the base model is a rip off, so if you want an Octo 3.2 GHz, then the Pro isn't looking so good.