I've owned every size of Mac laptop except 13": 12" PB G4, 17" Intel MBP, 15" Intel MBP, 16" AS MBP (my wife's), and now 14" AS MBP. I love small, powerful laptops, so I'm quite happy with the 14" MBP. It's certainly much easier to tote around than my 17" MBP was, though that was a nice machine for its time. I just didn't bring it to work with me daily like I do since I got the 15" MBP.
Your needs and mileage may vary, some people want the largest screen they can comfortably carry and don't care about power, others want massive power and a big screen, others want the smallest, lightest laptop possible... I'm happy with the smallest possible with the power to do the kind of heavy lifting I need, with photo editing, heavy calculations, and gaming all part of my daily use.