I just realized that this is the HD version, that's probably the reason I could enter.
But then again, seems you can't select the "normal" version from the giveaway page, strange.

I was not sure if you check all the messages in the giveaway, that's why I posted it here ;)

Edit: seems the HD version has twice as many achievements and twice the levels ... it's still a strange way to update a game, and there are already a lot of complaints from the community ... meh.