The spikes are high but your average is one hell of a lot lower than mine at this time -
http://www.thinkbroadband.com/ping/s...0-10-2011.html
From reading your earlier thread my money would be on incorrectly identified traffic leading to shaping and your frustration. It most certainly won't be the first time they've screwed up somebodies gaming. The numbers you've posted shows it uses similar bandwidth to high quality iPlayer - try that and see if it's OK. If it is then it's shaping or OnLive. If Onlive is working OK for other peeps then it just leaves the shaping.
Your upstream is high but still in spec I think.