There has been a lot of similiar Collector's Editions as you could've read this is what it includes extra:
- Bonus content includes the original soundtrack for all three games, three exclusive mini-games from thatgamecompany, a 30-minute documentary about Journey, Creator Commentary play-throughs of all three games, exclusive Journey PSN avatars and much more
- Also includes a 1-month subscription to PlayStation Plus
Also it includes 3 games instead of 1:
Includes three full games: JourneyTM, FlowerTM, and flOw
I don't see a lot of regular editions having this, really :p