Depends greatly on your usage/desired performance? That system can't handle games like Crisis nearly as well as an SLI'd Tri-GTX system with a QX9650 OC'd to 4.1Ghz and thats more "blowing money." That doesn't mean it's any less of a beast itself, but substantial gains can still be achieved for the price range under $3k. Also, if you're not going to utilize the SLI, drop the 780 board and go with a P5-E or something substantially less expensive. Also, differing hard-drive solutions are needed to meet the demands of different situations (sizes and speeds). Not to mention, you'll be needing a windows license which is another $100 minimum.
edit: (example)
Case: Antec 900
Power Supply: Corsair 750Watt
Motherboard: eVga 780i
CPU: Intel E6750
CPU Cooler: Zalman 9700
GPU(s): [SLI] 2xeVga 8800GTS(s)
System Memory: 4GB(2x2GB) Corsair XMS2 DDR2 800
Optical Drive: Lite-On 20xDVD Burner
HDD: Western Digital Caviar 750GB Sata 3.0Gb/s with 16mb cache
OS: Windows Vista Home Premium 64 bit
Price before shipping: $1722.90
After MIR: 1527.90
Some other options include changing the cooler for a thermalright solution (great coolers), upgrading the cards to GTS', upgrading to an E8400/Q6600 or upgrading to 8GB of memory. That system actually includes windows in it's calculated cost and is cheaper. Due to having included an after-market cooling solution in the cost, you can expect to OC that processor past 3.6Ghz without any problems. I kept a majority of the parts the same for comparisons. This list was made using newegg.