I got my Diablo III for "free". I signed up to the Annual Pass for World of Warcraft. My reason for it was since I'll be playing Mists of Pandaria when it comes out might as well have a free game.
Like others said Launch Day was a shambles until Blizzard employees woke up and a message appeared on the US forums about 10:30am PST (about 18:30 BST) about the login problem. I noticed it was working about 21:30 BST. So nearly 24 hours in Europe with the problem.
Mind you when has anything on launch day goes smoothly for online/mmo games?
We'll probably have the same thing again with Mists of Pandaria.
However now that I can play the game, I'm having fun with my Witch Doctor, firey bats AoE and rune enabled blowdarts firing 3 at a time. Only level 10 at the moment.
and killed the Skeleton King.