There was a DDoS attempt at this moment.
Recent connection issues and increased stales percentage were not caused by DDoS.
I really don't understand what anyone has to gain from these attacks. They don't bother me at all, they don't affect my mining income more than 1-3% a week, they don't lower the power of deepbit. Heck still hovering close to 50% some days.
Why does anyone waste their time? Silly kids these days.
They do cause fatigue damage to your hardware (when or if it causes failure is statistical in nature, but statistically it is very real).
Why take out pools? Well, there are many reasons why this happens. There are many financial and government institutions that would love to undermine bitcoin. There are probably plenty of speculators that lost big because of gambling money that they couldn't afford to lose and are now angry (angry types make mistakes and will get caught). There are people who spent a lot of money on mining hardware just to have difficulty prevent them from recouping their investment. There are probably individuals who mined a lot of coins early and sold them and found that the price went up so much that they could have made a lot more money (irrationally bitter). There are probably people that dislike individual pools for one reason or another and even some people that dislike the pools since it has largely eliminated solo mining. Lots of incentive, some financial, some political, some vengeful and some probably for reasons I haven't thought of. How many have the ability? Probably not many except perhaps the obvious (banks, governments, financial institutions and more come to mind with little thought). Bitcoin pools are the most attacked entities that I have ever seen since I have been using the Internet (1992).