many websites seem to be written using IE based protocols that mean they don't work properly (or at all) in Firefox, Konqueror etc.
It is up to us as individuals to make it clear to the websites in question that they are in danger of losing business as a result of their lazy approach to website design.
Email the webmaster with your complaint, explaining that you will take your business elsewhere, as you cannot access their website with your non-IE browser.
If enough people do this, then change will happen.
If no-one complains then the status quo will be maintained.
Of course, MS may just release IE for Linux
SD