I did try downloading the codec. It seems to work but it made my machine a bit unstable. After viewing a few movies in divX and suffering a few crashes I decided to uninstall it in favor of reliability. This could just be a problem with my machine but like turbo has stated, .avi's are sporadic at best in Quicktime and this codec doesn't seem to help much in that respect. It DOES work, though, if there's a movie you just HAVE to see.
just my 2 cents,
Bert da Troll