XSS, the new internet plague?

I'm obsessed with XSS, I can't help it. Whenever I stumble upon a new site I test it for common XSS attacks.
The real scary thing here is that most sites are in fact vulnerable. Usually I send the webmaster an e-mail, and I get a thank you wery much back.

Some weeks ago while trying to log in to my online bank, I entered the wrong account number and an error message was returned. I noticed that the account number i entered the first time was used as the field value on the new login screen. I couldn't help it, and tried with one of the most common XSS payloads: ">.
It worked, one of the largest banks in Norway, vulnerable to a XSS attack in the login screen.
I contacted the bank, telling them that i found a security hole. The next day some dude called and told me he should send my e-mail to the security team.

It has been 4 weeks and they haven't contacted me yet. So I guess my next step will to publish what i found on my company website. I don't like it considering the way to many back hats out there.