I regular visit different U2 sites/ Facebook, so I quickly found out about the presale - and luckily for that.
But I must say, there was a very, very short notice regarding this presale. The tour was - as far as I know - announced Wednesday and the presale started Thursday. Not very long if you are just 24 hours away from the internet (some people may even have a life).
Anyways, I certainly appreciate the opportunity to buy tickets earlier than others but I would also appreciate, if regular/old subscribers were notified just 2-3 days in advance.