I wasnt about yesterday, but I did hear from a friend at the time that 'parts of the internet had gone into meltdown'. I was dubious about her comment, but about a couple of hours later I heard from another source that slowness was being experienced via certain routing (peering?).
I believe that BT said that telephony demand trebled from normal during this period too.
Im afraid I cant confirm or deny because I didnt experience this first hand.