There is an open bootloader for pic called ZPL (zero pin loader), and an arduino-like system built around it called Dwarf Boards. There's a main Arduino-like board with the PIC and some headers that connect to shild-like daugher boards. It doesn't have a USB or Serial port, so you'll need an ISP, which is also available from the same designer (WISP628). And he provides a pascal-like programming language called JAL (just another language).
The website is www.voti.nl
I started out with PIC (and still have an almost full rail of 16F628A chips as well as a couple of dozen assorted other pic chips).
I've read that the pic chip architecture doesn't allow it to run c well at all (which leads to the lack of a gcc compiler). As well, the pic chips are simply less capable. For a given clock frequency, the ATmega can execute 4 times as many instructions. As well, ATmega has native multiplication which PIC lacks and there are other reasons the PIC simply can't handle what the Ardunio requires.
Out of curiosity, what are you interested in using the PIC for this? I was very reluctant to move to the AVR platform, but once I read about what Ardunio could do, and do so easily, I made the move very quickly.