Not sure what you tried, but they haven't fixed the problem. I just tried 100 different random 6-digit passwords using a python script over a one minute interval, then logged in to my account just fine using the web interface.
I'd post my code, but that would let any idiot figure out how to replicate this attack. Try including a user agent, and not using the same cookies every time.
I really hope that Virgin are not stupid enough to go after you in some lawyery way over this. I think you are already running a risk by disclosing this at all. The usual next step when a company doesn't show willingness to fix a security problem is that they try and shoot the messenger :-(
After reading down a few comments on the article you see that the write is talking about Virgin Mobile in the UAS, as someone in Australia points out that this doesn't work.
It would be nice if the writer of the article would have said that they where talking about Virgin Mobile US, as Virgin Mobile are a multi national company.
After a few attempts you can no longer use a PIN and must call in or use your security question.