Mmm.. harder to use just a standalone chip with Arduino -- they seem to require off-chip resonators and the like. So most likely I'd want a $19 board for each assembly, rather than a $6 chip.

But the board would save a bit of effort soldering, though so would a $4 solderless breadboard..

The programming language for Arduino looks a LOT like the C language, which is a major plus for me (I live in C).

Mmmm...