I strongly agree that the agenda must be published upfront.

Moreover, when something more substantial must be discussed, e.g. the accomplishment of some project milestone, or a work plan or a proposal for new features or for a new project, a document should be prepared and sent in advance to the participants with the description of the obtained results or of a plan or of a proposal, enabling them to prepare suggestions for improvements or for alternatives, or criticism.

Nonetheless, I may agree with what the previous poster said about Americans and conciseness in meetings (i.e. the lack of thereof).