However the the Arduino team, wanting a full open source platform, probably PICed (pun!) AVR because of the open source AVR/GCC C/C++ compiler that they could build on top of.
I have been burned too many times by closed source;
I don't know of any open-source PIC compilers (I would love to see an open source PIC Basic compiler).
There are no PIC Basic compilers
Worth getting philosophical about, since if you can figure out how to do it over and over again, you can probably get rich and solve all the worlds problems at the same time!
maybe we should get the Arduino team to help the US congress on a health care bill.
There is no definitive reason that an arduino-like system couldn't be build around a PIC instead of an AVR.