Good move by Microsoft.
Now they just need to upgrade their offerings.
It's probably much more expensive to buy the 'sales-right' for the title on the platform forever, to compared to a month/year - so when they buy the rights to give the title away for a limited time for subscribers - they can get a much better deal than with a permanent deal.
Nope, once purchased the button on PSN-store remain at 'free', if you search for the game after the promotion run out, it will still say free.
Back in the day, we used to have 5 downloads - but now it's limited to the two last devices the software were active on.
You can allways play it on two different platforms of the same type registered to your PSN-account, I think.
I think changes depending on the platforms it's available for.
So if you get a free PSP-game, wich you can play on both Vita and PSP.
I don't think the Vita adds to the PSP's - but once you download and run it on your third PSP - it will stop working, untill you log into PSN and deactivate one of your PSP's from your account to get it will start working again.
If you get a 'free' PS3-game - you'll be able to download and play it on 2 PS3's, once you get to the third, it will be dactivated, until you fix wich PS3's registered to your PSN-account.
Atleast that's how I heard it supposedly worked from people with 3 PS3's..
I have only had 2 PS3's, 1 Vita, One PSPGo and 1 PSP.
And the PSPGo and PSP I have no clue where is anymore.
So I can't test the limitations - but if the game is a plus-freebie once - and you hit 'Purchase' when the price is 'Free' - it will forever say free, as long as you are using the same account.
You might need to log onto Sony webpage and deactivate a system once in a while, if you use many different PS3's - but game should still be free.