Wow Blackhole is currently one of the worst malware running around. Since the attack seems to have been blocked there is not much you can do. You must have visited an infected website. Keep you computer up to date as well as your antivirus and you should be fine. But even if you had 42 software or hardware firewall protecting your computer you could get infected anyway. Antivirus are there to slow down the unavoidable. No antivirus or antimalware software is perfect. 0 days virus and malware are the worst. you will get infected even if you av is up to date.
that's stupid but if you dont want to get infected dont use your computer. -- - Technicien en informatique [A+] - Chasseur d'orage