It may be feasible for MS to bus additional GDDR5 in with the EDRAM design, but I have serious doubts as to how suitable GDDR5 is for the CPU. As has been noted in this topic, GDDR5 has highspeed prefetch at the expense of latency, so may in fact be a hindrance to the CPU.

Further to this, GDDR5 isn't a new technology and is widely extant on graphics accelerator cards. If it were a boon to CPU applications, i find it hard to understand why no manufacturer has used GDDR5 for main memory yet. It's not like there isn't a market for benchmark lovers with deep pockets, see the outrageous prices on top-end GPU cards.

The TGfx/PCEngine was an 8-bit design, so fairly impressive for what it was. The SNES was slightly gimped by the hybrid 16/8 bit CPU which was originally intended to provide backwards compat with the NES. That was abandoned of course. The Megadrive had decent silicon along with the two 68K/Z80 processors, but the SNES really had some fancy custom silicon.

I don't know all there is to know about tech stuff. But I do know a double standard when I see one

Years ago when Valve and other 3rd party developers spoke about the PS3 and called it a waste of time and hard to develop for, everyone was like "stop defending The Cell. The experts (Developers) are telling you whats what. Shut up fanboy." Or something like that. Strong words lol. Now... that the experts, 3rd party Developers are smiling ear to ear about the 8 GB GDDR5, I see some "who cares it doesn't matter derp-da-derp".

Odd. Very odd imo. First they were the experts. The people who knew what was best. Now they don't know anything I guess. So here's what you need to do...

Years ago and up till recently all the Developers (or experts as they were known until Feb 20th) they said "WE NEED MORE RAM. WE NEED MORE RAM".

So you need to walk into all those many companies headquarters and declare "IT DOESN'T MATTER. WHO CARES".

And they are going to be like "SAY WHAAAAAAAAAT"!!!

Then they will hire you because you know more then the experts.

I don't need to know more than anyone on this site or any other. Just need to know that the Developers (experts) know what they are talking about. If they say this is a good thing and are excited about it, then so am I

I remember playing Zelda: The Wand of Gamelon on my Philips CDi, and The Need for speed (in 3d), on my 3DO

http://www.youtube.com/watch?v=K_cVTBY0NoE

3DO came out when I was in 4th grade, it came out before PSX and SS, I remember that.  I can believe that it was the opening shot of the 5th generation, I just remembered my friend having it in 4th grade and it being both the most powerful thing out at the time and the most expensive.  So we are both 1 for 2 here, NeoGeo 4th Gen, 3DO 5th.  I considered 3DO 4th simply because it didn't do the 3D Polygon games as much, but that is a foolish assumption, the same as saying Wii and Wii U are not part of their respective gens because of lesser graphics, I stand corrected.  

We both learned something from this, nice.  

Freaky avatar by the way, I wasn't really looking at it for a while so I thought it was a real person, then I noticed the ears and freaked out a little bit. 

Maybe because the memory interface in all cpus (excluding exotic designs) is a ddr3 memory interface?

This is the simplest, most correct explanation on maybe all of gamrconnect.

I was also one that firmly believed it would be 4GB. 8GB just sounded insane. Even with all the history posted about Ram jumps being as big as 32x the previous gen, I just didn't see 8GB happening. Especially if the ram was really going to be GDDR5.

With low and mid-range gaming PCs currently having 8GB on average, but with Windows, firewall, antivirus and other services eating quite a big chunk of it, 4GB on a console, that optimises RAM a lot more, and native max res predicted to be 1080p in most cases, while on PC it can go up without waiting for a "next gen", could have been enough for another couple of years, but later it could have brought problems when porting from platforms with more RAM available, and this could happen not only from higher specced average PCs, but also from XB720. And should Sony launch last, porting from a 8GB XB720 could have given problems not only later, but just from the start. Bigger RAM can be quite a bigger cost initially, but its price drops quite fast, and luckily the times of RAM shortages and wild price rises, like it happened in the '90s and early '00s, affecting also XBox 1, are over. It's a good investment, as too little RAM could even prevent from fully exploiting all the computing power available, or make it at least more difficult, like it happened to PS3 and XB360, that had far less than half the RAM of the average gaming PC of their times, so they were undersized even taking into account the huge amount of RAM sucked by Windows on PCs. BTW also Wii's RAM was undersized compared to PS360, as if it's true that with SD it needed a lot less video RAM, system RAM requirements couldn't be much lower than on competing consoles, that already optimised RAM usage a lot more than PCs, this made ports of multiplats originally developed on PC or "HD twins" to Wii a lot more difficult and expensive.
Last but not least a generous RAM size allows to fully tap the computing power available, but once its size is "enough" for the console's commercial life, there's no need to increase it further, so it doesn't start a potentially money bleeding spec war, like it could happen with CPU and GPU. The boldest possible increase for 8th gen could be up to 16GB and even that would mean quite a heavy initial cost increase, but it would still be far from skyrocketing.

I think it's way to late for MS to change the configuration of there console. It would cost them a lot of money to switch the specs now and order new design implementation at this stage. MS will counter with there ace software.