I would say Microsoft has the least to worry about... 

Game development, particularly AAA (and even non-AAA core game) development is very risky (just look at how many studios have folded this generation) and Sony is going out of their way to take on even more risk in that department by aquiring new studios.  Next generation when game budgets increase it's going to be even more difficult to make a profit and the failures will be even harder for the money making games to cover.  Unless Sony plans on making a lot of money with its hardware which I really doubt they're in for losses.

As for Nintendo I think they're going to recover with the 3DS and to a lesser extent the Wii this year, but I think there's almost no chance of the Wii U hitting the ball out of the park like the Wii did.  Also part of Nintendo's problem is that after the huge successes of the Wii and DS the expectations for the company are now unreasonable and there's nowhere for the company to go but down.  They'll still make a yearly profit but I think they're in for some serious challenges in the future particularly from Apple but also in their glacial pace in adopting online gaming.

Yes, Yes! To NYANKS you listen!

I've been saying it for months: SON¥ is a business, not a charity. If every quarterly report shows your profit's going south, you're not taking care of your business. A free PSN is not a sound option if you're looking to make the PlayStation brand profitable and self-reliant. SON¥ (SCE) needs to become more efficient and productive. I mean, where the hell's SON¥ supposed to trim the fat? Price cut on an expensive console to manufacture, that for a very long time, it had to sell at a loss? On games currently selling at the same retail price as X360 games, in spite of the fact that they come in more expensive media (or give up on Blu-ray altogether)? Rid itself of profitable and competent first-party studios? No. Right now, the fat is PSN.

I think you are totally wrong here. There is NO evidenc e that sony will adopt a paying psn. The PSV from all reports will have free psn (or PSV equivalent) activity and having a pay psn system would limit crossplatform connectivity (as the psv and ps3 will have, and so may the ps4). Also sony will know that one major point of difference that may have added to the sales of ps3 would be that online is free. I dont see sony alienating all its fans who expect a free online system on a par with pc gaming by including a pay psn system. Finally, sony has attempted to garner greater profits with its own psn+ system which attempst to do what xbl has done for MS (though not as profitable). Point is It just doesnt make sense for sony to charge for their psn service - it will inevitably cost them but they have proven they are willing to take losses in areas to get better sales/profitability elsewhere.

It makes great economic sense to plug the leaks that are bleeding you dry. As I stated before, SON¥'s financial outlook (think globally) is dire and it's options are few. They won't cannibalize better performing consumer electronic divisions to rescue a dud; SCE must be solvent and self-sustaining. I don't see PS3 fans (especially PS3 fans) jump ship just because they have to start coughing up a monthly premiun to enjoy what, in theory could be, a new fantastic PSN experience, and SON¥ knows this.

As you well pointed out, 'they have proven they are willing to take losses in areas to get better sales/profitability elsewhere.' Question is: For how longer? Ask yourself this not as a gamer, but as an investor. SON¥ can weather the initial onslaught pay-to-play would cause among it's users, and still come out on top with a better more profitable product in the end.

It seems so!

I think you are making assumptions here. Sony certaining is making a loss at the moment but from all reports I have read the gaming division has been profitable in the last few years since the launch of the slim barring for this year (due of course to the tsunami and psn hack etc). Ergo, while sony itself is losing money the gaming division is a money maker and there is no reason for them go to a pay subscription system that may in the end lose them gamers. Also sony is a huge company - losses for a few years while not good dont mean that the company is in dire straits a fact demonstrated by the fact that the PSV will be loosing money at launch and estimates show that it will probably only return to profitablity in 2013. Clearly sony are not worried about loosing money even with all the problems they are having and are still willing to take risks (going up against smartphones) so its pretty clear they are not in dire straits.  Finally, sony are introduing the psn pass to get more money from the 2nd hand gaming market - while they wont make as much money with this and the psn+ promotions as xbox live they will still make millions and this should be enough to alleviate any need to add subscription service.

It would have been interesting to note how much more sales the xbox 360 would have had, had they gone with a free multiplayer system.

not really! xbox is just playing it safe with relying on multiplat's and focusing on kinect
nintendo are just having a little slumble right now! but they will get back on their feet easily
and as for sony did they loose their money in the gaming division? or was it the whose sony corp that lost the 191mill?