13" has better performance. If you don't care about performance, then what's an extra 2 inches to you?
Depends which model 11" you get as the ultimate is the same specs on both the 11" and 13"...
I have the 11" (i5/4/128) and my wife has the 13" (ultimate). Using the 11" all the time the 13" feels huge when I pick it up and use it and my old 15" laptop is just massive in comparison. I thought that going from 1680x1050 (on the 15") to 1366x768 would be a massive adjustment, but honestly I don't really notice it in day to day usage.
You really need to try both doing what you'd normally do.
I think it depends on your use. Do you plan to keep it in one spot (home or office), or take it around with you where ever you go? That would be the biggest factor in my mind as to wether to get the 11 or 13. I have had both, but finally I have the 11" with all the power! I have the ultimate and it's great. I take it everywhere with me. I have a protective shell "Speck" clear cover and use a sleeve in my briefcase. The battery life is better on the 13", but I love my 11".
Hope that helps you out. My personal vote is the 11".
13" has better performance.
Really depends on your situation and usage. A year ago I would have gotten the 13", no doubt about it more battery life and an SD port. But now I bring my laptop to work, bike + 1 hour train commute (where I use my laptop too). I also have a 19" monitor at the office that I plug my laptop to. So I went with the 11" because it is significantly smaller to carry.
Which do people think is best as It it is hard to choose
Thanks
Ian