For some reason, I’ve never come across the term “bikeshedding”, which someone used in an email to me today. From The Jargon File:

[originally BSD, now common] Technical disputes over minor, marginal issues conducted while more serious ones are being overlooked. The implied image is of people arguing over what color to paint the bicycle shed while the house is not finished.

Appropriately enough, the FreeBSD FAQ has a nice explanation.