After having this issue through closed beta and up to now I finally solved the problem. I upgraded my router firmware. This not only stopped the massive ping swings with accompanying rubberbanding and disconnects buts also solved the same issue with my PS3.
I hope this helps of few of you get playing. As a side note, make sure you follow the instructions on firmware upgrades very closely. it can be a bit of a pain if you don't know what you're doing.