I usually use firefox in my daily Internet usage, but if I'm banking or buying stuff I usually use IE because I in the past have experienced problems with limited support of firefox behind https secured connections by certain companies.

But according to this article IE had public critical vulnarabilities without fix patches for more than 9 months of 2006 whereas firefox only had 9 days.

The reason for this might / could be that approx 80% of internet usage are done using IE, and as such makes it more profitable for cypercrooks to create the vulnarabilities, but I don't care about the reasons!!! From now on I'm just using firefox and if it doesn't work I'll use IE…