The impression I've gotten from quite a few sites/articles is borderline fanaticism and your project just isn't cool unless you've bolted an Arduino into it somewhere. Just look at Arduino category at Hack a Day site. Even XKCD made fun of it a while back.

There are plenty of forks of the design as well now which vary by voltage, clock, type of AVR, number of headers, shape/size of board and position of ISP header alone so the "standard" isn't quite standard. Most people still don't quite grasp that AVR + serial bootloader = "Arduino" so they'll use the big board when not necessary and waste money + physical space.

Theres nothing wrong with the design and usage of Arduinos and I think its great that more people have found a cheap easy to program microcontroller.