Same problem as everyone else. Started Sunday, 1-6-12 and has happend for the past 2 days. Normal ping during the game is 60-70, went to 170+ and stayed. It seemed time based, I was playing earlier that day with no problems. Around 7PM MST the latency jumps and stays high.
Did normal TSing, reboot router, ensure nothing is being downloaded, called ISP, etc. Only with League, Counter-strike, and Dota 2 do not have high latency.
I have a friend in the same city that I play with regular that has the same problem, different ISP, only high ping with League.
Shaftz, did your problem get fixed?