hmm, i got bored with my Wii after about 6 years, so maybe like 2017 or 18. That would be fine with me. There's still lots of great ps3 games I haven't played yet.

I've heard this a couple of times, is there any proof or is it just speculation? Where do they lose money then?

I don't have proof of this, just a hunch I have. They're losing a tonne of money on it's TV business and some other departments. Gaming does make them a tidy profit.

Hopefully they either started on PS4 or started taking into consideration the possibility of developing on different/more powerful hardware. If they're 2 years into development and optimizing for PS3, most notably t3h c3ll, than maybe transitioning to PS4 would be very expensive. But it's price they should pay imo, it would be cheaper to make it on PS3 and it'll sell more, but on PS4 it will make Sony more money in the long run as it gets people to buy the system, which means more consumers using and paying for it's services and buying other software on top of the system itself. It would be a good move, I hope they see that.

Christmas 2013 or bust.

Sony have been making money on each system sold for a while now, that on top of the software sales and other paid services on the system such as Netflix and PS+, they must be making a healthy profit. Will it make up for the billions lost pre-2010? No, it they are now making money with Playstation. PSV should be just about breaking even or taking a small loss, software sales will make up for that and other costs such as R&D will be covered in 3 years according to Mr. Kaz Hirai.

Sony Bravia is a sickhole for Sony's funds, as was PS3 (was), and they're still making up for that, among other things. 

Fall 2013 is the most logical release date. They are not going to give headstart for MS again.

will be announced e3 2013 and released november 2014. my opinion of course

but they also said this:

“This time we’re not going to be late. We’re not late to the party at all. There is planning and development around certain titles and how it lays out in the future. I can’t speak to it really except to say we’re not going to be late to the party this time.” source

with wii U out this year they obviously won't be first.  but i imagine they'll be out basically the same time as MS.

I think the Activision contract kind of showed Sony's hand.  Bungie and Activision have no plans in 2013 for the PS4 with the game Bungie is working on, and no plans for the PS3 in 2014.