[ianjakobs]

13" for me. It's the sweet spot between it being portable enough to travel with or use while sitting on the couch but still having enough to comfortably work with. And then I have an external monitor at my desk for when I'm working. Those rumors about the MacBook Pro 14" would only improve it since the device size itself is supposed to keep the same footprint.

I had a 15" before this, and it's considerably more annoying to take with you. You might also be less flexible in terms of where you'll work from, e.g. if the table space is limited such as at coffee shops.