re: programming, it is a complicated
A lot of folks get their feet wet with an arduino or clone, but the latest source code is completely divorced from arduino, and the prebuilt hardware is not arduino. The prebuilt has a faster crystal (20mhz vs 16), only supports the atmega328 currently, no bootloader, no onboard serial or usb circuitry, pins dedicated to LCD/buttons/sensors.
For the prebuilt, and atmegas in general, avrfreaks.net is probably a better source of info.
FYI, I'm using avrgcc to compile and avrdude to load the chip and fuses, with an isp programmer, and a homemade clip-on programming adapter.