The article claims they’ve e-mailed who all they think was affected, so I’d suggest the following:
1. Double check your e-mail for notification
2. Login to their site and make sure that e-mail is what you have registered with them
3. Change your password on the site, and re-login with the new password
4. Change the password on any other site you used that same password
5. Be on the lookout for further notices
Good luck.
I’ve already emailed them.. thanks on the other info.