Diablo was bad but only for the very first hours. Obviously everybody had trouble when the game launched but from the next evening I don't think I ever had any issues. I think honestly it's because they don't want to spend money on infrastructure that will probably never be used again, since peak activity is usually in the first 24 hours and is much higher than the game will usually get again. Nevertheless, 11PM GMT has arrived and the servers are open, and I can't connect. To be honest I'm only in because I forgot the game was launching and noticed Battle.net was updating the game. On that note, props to Blizzard for letting us update the beta (120MB) as opposed to downloading the whole thing again.