When I go to "Information" on WipEout HD it doesn't say anything about an expiration date, but on all of my other PS+ files (Age of Zombies, Rally Cross) it does say an expiration date (15 months from now). This is all I have now for proof, won't be 100% sure until 15 months from now, lol. I think it's because it was a Demo + an unlock key. They can't time an unlock key, as it just automatically fully unlocks the demo.
SO unfair. I bought WipEout HD a LONG time ago at full price. Even bought the Fury expansion (which is WAY cool, btw). So all in all I spent $30 on WipEout HD, PLUS the $50 for PSN+, and now I find out that WipEout HD is a permanent bonus. Grrr! Oh well... nothing I can do about it now.
You win some and you lose some, sadly. I remember that I was going to buy PixelJunk Shooter. I decided to wait for months and months, positive that it would go on sale with the rest of the PixelJunk collection, but it didn't happen, so I bought it and two weeks later, it goes on sale for half off, and I could have bought two PJ games.
Same with Turtles In Time, I waited and waited, only to give in and buy it anyway, then it goes on sale a few weeks later.
You win some, you lose some.