Here was my favorite quote:
"There are already more than 115 community-developed applications in the Building Blocks catalogue, and more than 15 of them are open source. There have been more than 6,000 downloads of the Building Blocks SDK and more than 5,400 downloads of Building Blocks learning applications."
They fail to mention that you need to pay for Blackboard to be able to use these building blocks in it. And also, compare the number of downloads of Moodle modules on the Moodle modules and add-ons page, much more than the number who have downloaded these "learning applications."