xkcd vs. fruit

Today's xkcd comic features a variety of fruit arranged on a coordinate plane according to tastiness and difficulty. Here it is in case you haven't seen it already (click the picture to get the full-size version):



A few things that immediately come to mind:

1. What in the world are oranges doing on the untasty side?

2. Why didn't he differentiate between Colorado and non-Colorado peaches, or D'Anjou pears and Bartlett pears?

3. Seriously, what's the deal with oranges being in quadrant 3?

Here's how I'd arrange the fruit (click the picture to get the full-size version):