CPU Choice Dilemma...

In short if I'm able to sell my computer to a friend now, I'll be upgrading my motherboard, cpu, and ram.

My dilemma is; what to get? I do a fair share of video encoding with Adobe Premier and Handbrake.
From what I've looked up, you only get a 20-25% performance boost on the 6 more cpus over the quads like the 2600k and or 3770k.

Does anyone know if there is a possible 8 core coming out for the x79 chipset and will it be affordable? (~$600)
I've looked up benchmarks and it seems as though the 2600k and 3770k would be around twice as fast as what I have at 4.5ghz. and the 6 cores would be 2.5-3x as fast. (Can someone confirm?)

Basically I would like to get a really good motherboard and fairly good ram that does the job. (Not overpriced)
Then I would like to get the most cost effective cpu, and then maybe upgrade to an 8 core in the future if it looks to be a worthy upgrade.

Give me some ideas.
Thanks in advance!

I said above I do video encoding, but I also play games, but I don't expect to see much of an improvement in games.
8 cores as it will encode video faster, but maybe not worth it as it seems now.

The difference being from what I've seen in benchmarks, the amd 8 core can't compare to intel's 4 core when it comes to video encoding. (The whole point of getting an 8-core.) I already have the fastest computer of anyone I know, so I really don't need more bragging rights.

True, but we could still expect one in a couple years that will be cheaper and work with the x79? Guess that's really hard to tell though, right?