What's happening?

There doesn't seem to be any public information. The University's website
only says the talk was cancelled due to external reasons. The original post
in matware mentions "deals" and not "contracts," but there is also a lack of
details.

There is an official post announcing the relocation of the talk: http://losojosdetux.com.ar/2009/08/richard-stallman-en-ma...

Someone from the University's student association/group wrote something in
the comment section that indicates he knows more, but he didn't give out any
details. However, he left his e-mail address in the post: Cristian Baldini
<cristianbaldini@gmail.com>

The saddest thing here is that this is a tax-supported public University we
are talking about.