I think Microchip has made more of an effort to be hobbyist- and open-source-friendly than Atmel in several ways: 1) Microchip's IDE is cross-platform (Linu

I think Microchip has made more of an effort to be hobbyist- and open-source-friendly than Atmel in several ways: 1) Microchip's IDE is cross-platform (Linux, OSX, and Windows), while Atmel's IDE is Windows-only. 2) Microchip has a company-sponsored bulletin board on their web site for hobbyists (and professionals) to answer and respond questions. Atmel doesn't (avrfreaks.net is not associated with Atmel). 3) Microchip makes more microcontrollers in DIP architecture, which is useful for hobbyists; e.g., there are at least six Microchip microcontrollers with USB ports in DIP layouts, while Atmel has none. 4) At least Microchip is making claims about being open-source-friendly. I have yet to see Atmel mention open-source in their marketing materials.