Macbook Pro 13 inch w/ Retina Vs. 15 inch w/ Retina?

Apple holds the prize for the notebook with the highest resolution. And the second highest.

However, they are so far apart. One is for portability and the other is a workhorse.

There is the 13 inch with the ridiculous portability and the screen.

However, there is the 15 inch. With the quad-core i7 and all that RAM. It is still very thin for the amount of power that you get in the actual laptop.

The problem is the portability. Will the 15 inch be easily portable and will the 13 inch be underpowered and not perform on the everyday tasks?