Cookies have nothing to do with it
Good (never have trusted them), i was thinking that login fails on sites that haven't been exempted in my proxy filter (privoxy) may have been due to a cookie not returning, or being confirmed to the sending site. On reading the config again, it does use the word "persistent", hmmm, so the sites just reading it from my end, ok ...
But, does that mean stats are gathered via a bot reading site logs. Would have though they would be locked down.
But as you mention ...
The sites you use the gather the statistics also affect the results. msn.com will get a higher proportion of hits from IE than mozilla.org, this site or Slashdot.
It also depends on how selective they are. Advertising does work though ... lots of people will make a choice based on percieved popularity regardless. It can put to test all that a person thinks/believes sometimes.
The FVWM wm -=- www.fvwm.org
Somebody stole my air guitar, It happened just the other day,
But it's ok, 'cause i've got a spare ...