I'd like to make a suggestion for Paint.net 3.5 or 4.0. The polygon selection tool of Photoshop or Microsoft PictureIt! ect. When I used to use PictureIt! I used this tool all the time becuase Magic Wand was not accurate enough and Lasso was impossible to use accuratly. I know there is the method of using the Line Tool on a seperate layer and then using the Magic Wand to select what you want, however this is not the most glamerous of methods nor the most accurate.
I think this would be a great addition to new versions of Paint.net.
Keep up the hard work guys!