I can't find any public reports topping ~100 Gbps. For example, here's a recent article that interviewed an Arbor employee and mentions a ~100 Gbps plateau:
Hrm, maybe Im misrembering. Found akamai claiming 125Gb/s in '09, and some more arbor quotes of ~110Gb/s. I'll see if I still have the report Im thinking of tomorrow.
http://wwwns.akamai.com/rsa_2011/RSA_NOCC_DDoS.pdf