Your choice of hard disk is good, but this one is a little smaller, costs less and benchmarks faster then your choice and benches just under the WD Raptor's here is my selection; Western Digital Caviar Black WD6401AALS 640GB 7200 RPM 32MB Cache SATA 3.0Gb/s Hard Drive - OEM
Memory wise, I prefer OCZ. My selection is a little more then yours but is also 1600 opposed to the 1333 and faster timings at 7-7-7-24. With the hard drive I choose, the monies saved for the faster drive will enable you to get the faster memory while still saving money.
http://www.newegg.com/Product/Product.aspx?Item=N82E16820227381&Tpk=OCZ3P1600LV6GK improving overall system performance and stability while OCing
Good choice on the processor and not getting the higher end CPU's. The 260 will go to 3.8 on air with a good Heatsink and Fan for a 24/7 oc with the above mentioned memory, anything higher and your looking at possible heat issues for a 24/7 (when under stress) without alternative cooling.
I would look into the OCZ Vendetta 2 with the i7 adaptor for your heatsink and fan. Your choice is in last place for cooling Source:
http://benchmarkreviews.com/index.php?option=com_content&task=view&id=266&Itemid=62&limit=1&limitstart=10 read this page and the following four using the NEXT link at the bottom.
Mixed reviews about this MB, I have never had personal experience or know anyone who has so I can not comment on it. Personally I don't like the 4 slots for memory over the 6 on almost every other X58 board. In addition you could never go Tri SLI since there are only 2 slots. This is the entry level X58 board being the least priced board of all the manufactures. You have a good build on the way and another 50.00 to 100.00 into the MB would go a long way in this level of build. The MB is the (IMHO) second most important component of any system following the PSU. For future upgrades this would make sense too. Most don't mind adding memory, a second or third video card, swapping out CPU's or PSU's, but a MB is kinda like a complete rebuild. Your system is only as fast as your slowest component.
Finally, I would suggest at least an 800watt PSU