I am employed by a corporation that is undertaking a project to remove
malware from our end-users machines.  In the IS dept where I work we
support around 1800 users.  Most machines are now running either
Windows XP SP1, or Windows2000 SP4.

Start off with some statistics.
By how much has malware on the internet increased in the last year?

-What are the TOP reasons why computers today become infected with malware?
From your research would you say that it is:
1.) Improper ActiveX control settings in common browsers.
2.) Users installing programs that come "bundled" with malware.
3.) User ignorance (ie: installing shady browser toolbars [yours excluded])
4.) Or some other reason.

-By what methods are corporations dealing with this increase of
malware on the internet?
1.)Tighter Active Directory group policy.
2.)Change in browser ActiveX security.
3.)Third Party software.
3.)Written company policy.
4.)Some other solution. Please describe.

-Which companies provide Enterprise level solutions (Top 5 or so) to
this emerging problem and what are their products called?  Please
include short descriptions on the key features of each product you
find along with links to their pages.

Please include a list of sites that you found helpful or interesting
regarding this topic.