When are they going to shut down psn for the ps3? I doubt they ever will, same as Xbox Live for the 360 will never go. If people thought the PS2 had an amazing lifespan past it's generation they haven't seen anything yet. By the time that PS+ stops getting free PS3 games, there will be some for the PS4. That's if they ever stop getting them, in 4-5 years time even games like GTA V will probably be on there.
PSN for PS3 and Xbox Live 360 side wont be around for ever. Especially with Microsoft, take a look at the PC section if you are not aware with what's happening there
http://forums.overclockers.co.uk/showthread.php?t=18535618
Games for Windows Live will be discontinued on July 1, 2014 and people are kicking off because all those games which has been given way for free or they have brought off the Marketplace now run the risk of being unable to access the games after the service has been shut down. Some games will be still access through updates but some companies no longer around such as THQ, leaving their games dormant.
If you honestly believe Sony will give away free good games (such as AA titles) for the PS4 as part of PS+ like they do on the PS3 then you need to think carefully about their strategy.
Sony launched PS+ because they saw Microsoft charging for playing online and making shed loads of money out of subs especially when a new Fifa or COD is released. Sony saw this and wanted piece of the pie, so they launched PS+ with small features such as Cloud saving, scheduled updates etc. Minimal took it up as its was pants paying £40 a year for such little service. So the only way to get consumers interested into PS+ is to offer good free games. Then PS+ was brought to life and PSN was full of consumers playing online more than before.
Now, when Sony announced PS4 they said, you need to PS+ to play online apart from with free to play games. Not many, if any at all questioned "why do I need to pay to play online with the PS4 but I didn't with the PS3?" Because Sony have blinded consumers with the free games you get on PS3 with PS+ and it has over shadowed the requirement for paying the sub for playing PS4 online.
So why would Sony offer free games on the PS4 like they do for the PS3, when consumers have already brought into the system with PS+ from the previous generation?!?! Also why are the free games no longer accessible unless you sign backup to PS+. In a few years time when eveyone has moved onto PS4 from PS3, Sony wont be offering free games. Why would they, they dont have a reason to anymore as everyone is paying for PS+ on PS4 to online play only. Which is what Sony wanted from the start. Then Sony can announce in a few years time "Due to lack of players on the PS3 platform we are shutting down PSN for PS3 after XXXX date" And you are stuck technically paying the same for less on the PS+.
As for the Vita, again great offering free games but you need took a the ratio of, the amount of free games they offer, the size of the games and how much you are willing the fork out and buy their over priced memory cards to fit all those games on, compared to buying the physical game on the cheap. Yeah, its good we can download the games over again but I have 120mb virgin connection and it look over hour to download a 1.5GB game. Thats crazy compared to downloading a game in minutes of the same size to my tablet devices or phones.
Sony have a history of boasting about something good to get consumers attention then take it away later down the line. Look at what happened when Sony removed the Other OS option from the PS3 and the amount of fuss that kicked up. Sony's excuse....."Because of security reasons" What utter nonsense!! They used the OS Other option as an selling point against the 360.