Yes, razoreqx has a good idea, and in the mean time you could wait until the block has been lifted with a coming update.
Blacklists can not always reveal the actual situation of a website. Some blacklisting is obvious because the AS and the domains there are on a so-called eternal list (baddies by intention), cleansing has become overdue and the site is malicious and will launch malware all sorts. Then there are mass infection schemes that infect a lot of good web rep sites at once and should be blocked as long as the infection is there. Then sites have been cleansed or redirects are no longer active and the blacklist has not been lifted yet. So one thing you did, reporting here and to avast is the best thing you could do.
you can report it here http://www.avast.com/en-eu/contact-form.php?loadStyles