I've worked in 5' tall cubicles, open plan, shared office, and private office. I've also worked in the computer room itself (not nearly as fun as you would think).

I have to say for me private office is the best. I can concentrate on development, and if I need to have a micro-meeting the people I need to talk to are just down the hall. 🙂

Plus, if I absolutely need to remain uninterrupted I can close the door and set my phone to "busy".

Ah, development nirvana...