I also have to say that IB's current performance is not acceptable.
However, considering the last years, I am still a very satisfied customer.
One has to admit that this incredible surge in volume was completely unexpected. If someone told me a week ago that 10 million ES trade within 3 days ... you know ...
So, I think IB has to learn from this. Most likely, it means: more servers, more bandwidth and more stability/stress tests