Biggest potential weakness is no one may take the task to develop accessible games for the new generation of gamers, so in the long run even if they steal M$ marketshares the market will decline.
In other words, Sony will get a bigger slice but the cake may get smaller.

It's weakness is its reliance on electricity, unplug the bitch and it can't function....and you win!

Nope. As long as its fans have unwavering belief in it (and Sony), and sales keep up as they are, it has no weakness to speak of.

Japan

Have you been living under a rock?

And yet, MS doesn't have the balls for long term investments, subvention and is not as generous and rewarding when it comes to online service.

No?  Show me where the PS4 version of a game is VASTLY better than the Xbox One version.  They're not.  Sure, they perform marginally better on the PS4, but largely the games are the same.  I also stated 'If true', since that particular article didn't have a named source.

I'd say the largest weaknesses (Sales-wise of course) are the fact that they aren't as appealing to casuals (PS2 had its DVD player, Wii had Wii Sports...) and that the first party software doesn't have as much brand power

Define VASTLY better. It's not like having a perfomance gap between a 1000 $ and a 500 $ hardware.

You wrote: "Alarmingly, one source has suggested that PlayStation 4 version of cross platform titles could be “castrated” so both versions of the game look identical. "

But what we have seen so far isn't identical. So at what point do you suggest will the "castration" start? Must be very soon, because the "resolution damage" has already taken its toll.

The biggest weakness of the PS4, hardware wise is the DS4's battery life and maybe the stick's plastic (I am not affected by it, but I have seen one or two demo units that have it... so my guess is it's a problem).

Software wise, I will wait until Sony release their first feature update, with DLNA and we will see, I think it's pretty solid.

The games are amazing so far, I have not been back to my PS3 or PC much since I got it... not for serious gaming sessions anyway.

I would like to be able to upgrade the APU in it from time to time but it would make it too much like I PC I assume...

The problem is your using subjective terms to qualify the disparity. Lets consider the facts here.

Generally speaking for the first half of the previous generation, the 360 out did the PS3 on multiplat games, usually because the games got ported from 360 to PS3 and the Cell was difficult to work with (Unless you're Hideo Kojima)

However, the disparity was within a few frames. Both had resolutions at 30fps 720 or lower for most games, with PS3 being more choppy then 360. For a gap of 200, at the end PS3 tended to have better looking multiplats so the disparity was basically eliminated. 7th gen was arguably the larger disparity in performance for price

Now we have a hardware disparity (which cannot reasonably be overcome with software alone) leading to consistent game disparity of about twice the frames or twice the resolution and the price disparity again.

Thus the Gap b/w the PS4 and Xbox1 is larger than the 360 and PS3, and it would be even larger still if the ps3 didn't cost 600$

Since PS4 has a larger marketshare, is easier develop for (for virtue of not having esram), and fanboyism has no place in business decisions, Xbox1 games will probably be ported from PS4 if not on PC first. Downgrading a game for the illusion of parity damages the perception of the game, this is why the PC version of games will usually be the trailer if it looks better, and why we aren't seeing the 360 version of Titanfall, along with the fact that MS wants it to sell more XB1s