the only reason why its that small is because it has very few keyframes which makes it almost impossible to jump through the file and causes nasty quality ... cant think of any codec which has blocking issues as bad as wmv
plus id consider wmp10 (or whichever version theyre at) untrustworthy software
and yes divx has gone downhill ever since they got the idea to make you pay for it
conclusion of all this is use xvid for smaller resolutions and x264 if you want high res at a sensible filesize
although i understand that wmv has advantages when it comes to reaching a larger base of not necessarily computer literate viewers
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