This book contains an extensive series of case studies of designing space for learning and doing knowledge work in schools and universities. If you accept the premise that much of the work that will take place in Enterprise 2.0 organizations will be knowledge work, then you may find these a source of ideas and insights.
Diana Oblinger (of Educating the Net Generation fame) has edited/released a new book: Learning Spaces (not sure how long it has been available, but it has been referenced by several edubloggers over the last week). I love this quote: “Spaces are themselves agents for change. Changed spaces will change practice”. The bulk of the book consists of case studies of learning space design in different organizations.