Is there a big difference between 8gigs or 12gigs of Memory for video editing?
 

Say you're you're editing and rendering a 5 minute video everyday.
Will the 12 gigs of memory be MUCH faster than the 8, or barely noticeable?

you will not notice it at all, Fast ram is better than more ram.

awesome thanks a lot. I just got a refurbished laptop with 12gigs memory and edited a video, it edited very fast faster than my desktop, but its having problems with the hardware and Im going to return it and get an 8gig system but new and not refurbished.

CPU and GPU surely plays a much more important role...

This. Get a decent nvidia or ati and use GPU acceleration, it's great.

Just a reminder, Adobe Premiere, After Effects or any other Adobe program will default with 4 gb of ram to be allocate to the program you are running, however, it will also utilize that ram up to 64 gb.

My system is 16 gb or 1600 mhz ram and it is noticeably faster than when i was editing video with an 8gb system, of the same speed.

You are not going to get any real rendering speed out of a laptop. That's all there is to it. You are not going to notice anything above 8 gigs on any Windows machine for one program. 8 is the sweet spot. If you like to open a ton of windows and programs get more ram. If you like to render efficently, get a desktop.