IE6 at work & IE7 at home. Both are affected but IE6 is the worst affected!!
Danny, whilst I fully understand why you want the google revenue to help fund this site (and have no issues with that whatsoever), your post around changing to FF instead of IE is not that realistic based on the fact that a lot of the logins to this site are probably from hotels or through work machines where there is no choice as to browsers. As I would guess that your direct revenues (i.e. banner ads) will have some basis on the amount of page impressions per month (which has an impact on indirect revenues via click throughs), you want to make sure that you don't affect what is undoubtedly the majority of the browser market (even if it is crap
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