Maybe I'm a bit old fashioned, but I believe resumes should still only cover a single page. Today's managers are too darn busy to filter through the clutter when it comes to deciding on who gets an interview call in or not. The last thing they want to do is try and locate that second page.
I look at it as an exercise in brevity. What's really the most important thing you have to communicate when looking for that perfect job. Pairing down my 25 year experience to a single page wasn't easy.