Have you noticed an appreciable effect whilst playing?
I would posit that it's not the small ping increase that's the issue. More likely Virgin's admission that you're in a "high utilisation" area. Try the thinkbroadband speed tester and note the buffer bloat results. You could have the fastest gaming router set up in the world, but if the delays are ISP side you won't be able to odds it.
I'm not familiar with Virgin. Do they supply a router? Either way, make sure you have QOS active in the router settings (if you haven't already).