I just read about Sony's newly announced crossbuy feature. What I could not retrieve from the articles is if this feature is only for online bought games or also for games that have been bought in a real game store? Had Sony disclosed any info about this?
Yes, it will be for games bought in stores as well. See here:
If you purchase either a physical or digital version of an applicable PS3 title, you can download the Vita version at no extra cost.
Please note, however, you get a PSVita copy of a game when you buy the PS3 version, but not the other way around.