Telecommuting is often portrayed as the great innovation and if only unenlightened companies and managers would permit more of it the world would be a better place. However, something is lost: tacit knowledge and productivity decreases.
Andy "Sandy" Pentland gave an interesting talk on the Reality Mining for Companies, or, How Social Networks Network Best at the 2009 O'Reilly Media Where 2.0 Conference. Technology now allows us to measure social interactions much better than before -- where are the people and what they are doing -- and the results are surprising. Instead of speculating whether reorganising a seating plan improves productivity, we can now measure it.
Although technology can give us the same access to explicit knowledge, the decrease in tacit knowledge (which is usually not measured) has a large negative impact on productivity. For example, face to face contact, having coffee and lunch with colleagues significantly improves productivity.
I'll remember that when I have coffee and lunch with my colleagues tomorrow. I do great things at work, and I credit that to the great people who work with me.
The above link has a video of the talk, but an audio only version is also available from IT Conversations.