To illustrate, I just counted over 30 games in my available downloads for the PS Vita - everything from PS1 classics to current AAA titles like Uncharted.
I do not own a Vita.
But thanks to my continued PS+ membership, if I ever do get one, I'll instantly have dozens of games to play for it out of the box. (And that's not counting any bundled games that may come with it - or any additional games I'll get thanks to PS+ between now and then.)
There is a reason Microsoft had to change Live Gold. It just wasn't in any way competitive.