Frances Bell

Two important issues are:

who makes the decision?

and what are the constraints?

Not from USA but here is an interesting example of UK schools having to choose from an 'approved list' http://moodle.org/mod/forum/search.php?search=BECTA+list&id=55 

The issue then becomes the politics surrounding getting on to the list.

How about maximum one (greatest value) listed? That would eliminate multiple links.
I think it's difficult to make moral judgements about the businesses, but you could exercise some control over the wording on the link.

The 'link whore' approach does seem to be multiple links for 50$ donations.

I can assure you that Blackboard is not practically compatible with Firefox since it regularly falls over when you try to do anything interesting like upload things.

I have had this experience with Blackboard Blackboard (as an instructor) and WebCT Blackboard (as a student) ;-(