The biggest and meanest (and not completely legal) codec packs of all got an update! It contains new versions of MPC, ffdshow, XviD, DivX, Haali Media Splitter, x264, AC3ACM, FLV splitter and InterVideo DVD decoder. Just install it over your current installation.
>> Download K-Lite Codec Pack update (27/06/2006)
>> K-Lite Codec Pack website