This particular website is laden with SciFi books and gets hit from worldwide, so it’s got a good — but conservative — visitor set.
Of the 1190 hits since Sunday morning, 1189 were advertised as from Windows users, and 857 claim to be from MSIE, leaving 333. One of those is an OS/2 user (or says (s)he is, anyway), the other 1189 claimed 'Doze & 257 of those are Firefox... so:
MSIE = 72%
Firefox = 21%
Netscape = 3.5%
Opera = 2.9%
Other = 0.6%
I’m sure that there were other Operas masquerading as MSIE under Windows (it’s the default setting), so from this, MSIE has less than a 72% market share.
Granted, the data filtering is pretty shonky & all, but these are real, non-teed-up figures. I’ll watch it for a month before telling you rowdies where it is and mucking the tallies up.