way to miss ALL the marks...
News flash, those newer HDD are not for being faster, they are for cramming more space... we just hit 1.5TB HDD and they only cost 200$
The SPEED based drives are the SSDs and the raptor, and intel just conroed the SSD market... where, the greatest upgrade people could get now is an intel SSD (but it is too expensive right now)
The extra ram would not just help, but is absolutely NECESSARY for video creation, because every model on the screen takes an amount of ram. If you run out, you can't encode that scene. And vista speedboost makes use of unlimited amount of ram to cache your programs.
And the new 600$ video cards are faster then ever. The 4870x2 is way more then TWICE the FPS of the 600$ 8800GTX from last year. and NEITHER is enough to reach even 30FPS (min playable) on max settings in many modern games. Not "over 100FPS"
And lastly, you said your main goal was reencoding video.. well, all the things above don't really matter to that... except that now we have GPU video encoding that is several orders of magnitude higher. But also the CPUs are getting massively faster, since video encoding scales really REALLY well on multiple cores. The wolfdale brought SS4 (60% faster divx encoding) and also a native per clock 60% increase in divx encoding... 120% ish increase in encoding performance... Take that to quad core and you have some fast encoding...
The last game I saw a huge change in was level loading in NWN2... where going from an Athlon 64 X2 3800+ (2ghz) to a E8400 wolfdale cut down my level load time from 1/2 to 1/10th depending on the graphics settings (I know it does not make sense, it is not that much faster, but I measured it and it did... I am guessing something else was involved, it is a very inefficient game at level loading,all I changed, mobo + CPU that is)