Internet Explorer's market share has reached an all time low, falling below 60% in April with Firefox and Chrome steadily increasing their share.
According to Conceivably Tech, Internet Explorer users have declined since August 2009 by nearly 10%, while Firefox users have slightly increased by 5% or so, with Chrome taking a leap and increasing to a near 10% market share.
But Internet Explorer is old and sluggish. It occasionally pees on the rug, and you have to take it for a check-up every few months - and it always ends up costing you dearly. It's a bit like an old dog which you have, and you care about, and will sincerely miss it when its gone, but it's starting to become a bit of a burden.
For the home user, there are two sides to consider:
Advanced users who do care about their browser, and are shifting away from Internet Explorer for their own personal reasons.
And as I have said before, for university environments, it's far simpler to keep Internet Explorer as default, with access to other browsers as well. But even today, I still cannot pinpoint a particular, specific reason as to why it still holds so much sway in the corporate environment.