We are already using Windows 7 Enterprise Ed organization wide on our laptops & desktops with AD & Exchange on Windows Server 2008. Its performance is phenomenal and has increased overall productivity ever since persuading even Linux users to migrate and the overall feedback is inspiriting. Moreover, a few trainings that I imparted to organizations upgrading from Windows XP/Vista, individual and collective response is quite positive. Before anyone would call me a Windows fan, I must mention that I am Linux certified and have been using Linux for almost 10 years now. Ease of use, GUI, media center, quick search and driver support is pretty neat while the OS is less resource hungry (works like a charm even on low-end hardware) as compared to it's ancestor; Windows Vista. Thumbs up for Windows 7, I say!
Windows 7 rocks. I started running build 6801 since October of 08 in our lab and plan on rolling it out enterprise wide by the end of Q2 of next year.