OMG!!! It's a Mac Attack! Seriously though, the idea changing the icon is actually rather sound. I had added Paint.NET to my explorer bar and it looked almost like a teardrop; it was difficult to even notice what it was. However, the new icon, as "Mac-ish" as it seems is a little more intuitive.
BTW, any chances that future versions of Paint.NET will support the creation of icon files?