I found the neatest article on Yahoo about why we don't telecommute more:
http://finance.yahoo.com/columnist/article/moneyhappy/7928
In a nutshell, we think we're happier because of the social aspect of being onsite. And for some people, the social aspect is vital. This really comes down to that lesson of know thyself.
Telecommuting is a great way to get caught up on work, as you're away from the majority of distractions. Full remote work is not for everyone. Partial telework is an ideal balance in that you can stay in synch with your coworkers, and yet you also can work from the home office reducing wear and tear on everything.