Stock goes up and it goes down. There are many reason why a stock may fluctuate, there is too much information out there to really pin point the cause. You are stating that Investestors are paying close attention to the cost of the ram, while I can counter with the fact that the stock market is ruled by computer algorhythems that make little sense to outside parties. I can also counter with the rapid decrease is cost of ddr ram once the initial fix cost are paid for and production & large quantities is bound to drop prices which could be good or bad for Sony if they are buying them are market price. In reality I don't know what type of contract/deal Sony was able to make with its Taiwanese partners, and I'm sure they are keeping those secrets tighter than their console specs & designs. 

There will always be some type of speculation when new products are introduced in to an ever-changing market; you telling everyone that Sony's Stock went down when the announcent of the PS4 Ram was announced made look at the price. It's currently sitting at $14.01. Down a wapping .50 cents from 21st of this month. True its is about a 3.5% decrease, but judging from weeks past, this isn't all too irregular for Sony's Stock to be fluctuating at these rates. You may be reading too much into someones observation man, or your observation is limited by your own narrow views.

This. The specs that we've heard thus far will most likely stay the same.

your reply does nothing to contradict what i said 

the extra RAM was installed because of the requests from developers

are you implying that you have a better understanding of the requirements for their games than the developers do?

If I was a developer and had 4GB to work with and someone said I now had 8, I would obviously say I like the fact I have more.

If I was a developer and had 8GB to work with and someone said I now had 16, I would obviously say I like the fact I have more.

If I was a developer and had 16GB to work with and someone said I now had 32, I would obviously say I like the fact I have more.

If I was a developer and had 32GB to work with and someone said I now had 64, I would obviously say I like the fact I have more.

The less a developer has to worry about anything makes it better for him. If Sony actually increased those 8 to 16, you probably will not see any developer complaining. But it will be terrible for Sony as the cost will go up and the results developers will get from the extra RAM will hardly be noticeable.

I bought my PC with 8GB of RAM. For a PC, that is currently a sweet spot. If I increase it to 16GB, for the stuff I do on it, I will see no increase in performance or quality of my games. I will get absolutely nothing out of it as I use at most 4GB of RAM. If I paid for more ram, I would get absolutely nothing out of it. Should I buy it then? Of course not.

The real question is if it's better for Sony.

BTW, this is diminishing returns: http://i.imgur.com/ChsSwUE.png

That's minor changes... the project is already defined... the CPU, GPU, 8GB GDDR is already confirmed and that's will not change.

I can see a minor change in the clock of CPU and GPU... that's easy to put the GPU at 850Mhz and give us 1.96 TFLOPS.

...now you're comparing arbitrary amounts of RAM to what devs requested

and yes i already knew what diminishing returns is but obviously i can concede that devs know far better than i do about whether their games have reached that point or not

The PS4 specs are all the devs are asking... so Sony will not change that.

No DVD, No eDRAM, no Bad Gamma, no PWL

Yes 8GB RAM

The only thing this rolling spec says to me is that Sony's only engineering goal is to trump the Xbox' spec. This is bad product management and leaving considerations like form-factor, power consumption and heat-load as last-minute considerations. Sony can't afford to finance another overpriced console, nor can they afford a reliability issue. So it's no wonder that investors would be nervous.

I know what diminishing returns is, but I wonder how well this concept can be applied to computer hardware when it is custom made (key word here) for a particular purpose. One usually uses this term to define people in a company; as in how many unit of labor a company needs before it is no longer profitable for the company. There is a formula, and a curve composed of calculus limit formulas. I don't know if this applies to circuitry though.

However, I do know of the word Bottle-neck too which usually is more common with technology, where one piece of hardware hinders the other components, as seen in computer hardware. In my opinion, It's too early tell if any of the components are going to hinder any of the next generation consoles, and it appears that Sony has been developing this machine for quite some time. So only time will tell.

Bolded 1

That is because you would still be running the same program. If you run a static program it will hit a point were more power does not make it look or run noticably better. This is not the same as giving devs more RAM. Giving devs more RAM means they can add more to there program. 

More RAM for devs means:

-Added effects
-More animations
-Higher res texture
-More NPC
-More detailed enviornments
-Longer draw distances

There is plenty more that they can do with extra RAM in the development of a game.

Bolded 2

Games are not running on 1.5GB of VRAM because they can go any higher, it is due to PC games being restricted by the mass market spec. Right now games are built for PS3/360 and low end laptops. They are then scaled up from there for things like the GTX 680. With the PS4 and hopefully the XB3 having 8GB of RAM this will give devs a new mass market spec. 

GPUs with 3 and 4GB of RAM are fairly new to the market, and they will start to see that be used very soon. It will not be long before 6, 8, 10, and 12GB cards are on the market. By the end of this gen you will see games running on much more VRAM. 1080P PC games will probably be using 8 - 10GB of RAM, and we will see 4K resolutions pushing 16, and I feel this is a minimum.