Well Dave, Mark’s comments seem directed to the educational industry.
You’ve suggested three reasons for business to adopt open courses: strategic planning, training and research. I won’t speculate as to what interest business might have in opening those areas up.
Have you thought about plain-old product advertising and marketing? It seems that twitter, blogs etc. are great for advertising and marketing educational industry product (e.g. ‘open courses’). Would these affordances work for business products? Could twitter/blogs etc. used in open courses help to advertise and market a business product? You’ve hinted at this a bit in terms of ‘branding’ and community.