Your build that you linked is a bit overbuilt 
Here is a cheaper but still very kick-ass build instead. Dropped the super fancy case and power supply to reasonable ones, scaled the GPU down to a 960, brought the RAM down, added a HDD, removed the unnecessary sound card because integrated ones are fine, and gave you a PCI wireless adapter so you don't need to run an Ethernet cable across the house or use a junky USB adapter.
http://pcpartpicker.com/p/V8Nh8d for only $897 before a $55 rebate)
The TV looks fine, it has 60 Hz refresh, which is fine. You don't need a 120 Hz screen unless you want it, and 30 is too low
All you need is an HDMI cable from the GPU to the TV.
(you can drop the HDD, but you should keep the PCI Wifi card)
Here is a cheaper but still very kick-ass build instead. Dropped the super fancy case and power supply to reasonable ones, scaled the GPU down to a 960, brought the RAM down, added a HDD, removed the unnecessary sound card because integrated ones are fine, and gave you a PCI wireless adapter so you don't need to run an Ethernet cable across the house or use a junky USB adapter.
http://pcpartpicker.com/p/V8Nh8d for only $897 before a $55 rebate)
The TV looks fine, it has 60 Hz refresh, which is fine. You don't need a 120 Hz screen unless you want it, and 30 is too low
All you need is an HDMI cable from the GPU to the TV.
(you can drop the HDD, but you should keep the PCI Wifi card)