Wow - this is quite amazing. It's in French, so run a translator on it:
http://forum.ovh.com/showthread.php?t=77054
The owner of OVH is saying that their traffic has increased 10-15% (60-70 Gbps) yet their number of clients has stayed the same and that their only explanation (since nothing else has changed) is that with the closing of megaupload, their bandwidth has been re-distributed and OVH has taken a part of it.
60-70Gbps gain just for one ISP by the closing of a site.
