I am currently studying at the graduate student of informatics at the UvA. I am enrolled as a masters student in business information track and my experience so far has been great (although it has been just a month).
The lectures are well structured (a theory class followed by a practice session during a week for each course) and designed in a way to accommodate part time students as well. There is a lot of self-study needed and you would be involved in numerous assignments (group and individual) like every other masters course, but the special part here is the choice of electives and your topic of thesis (with extreme flexibility).
As a tip – be well assured of which track you want to specialise in. You can find information about the different tracks and other courses on the university website (which is pretty thorough and provides you all the information that you need).