On March 24, a post appeared on the Code Anthem blog titled "Don't Judge a Developer by Open Source". Since it starts by saying that the authors are big fans of 37Signals, I skipped over it (I'm not), but when links to it started appearing elsewhere, I went back to have a read. The post's thesis is that judging developers by looking at their open source contributions is a bad idea. I've been doing that for several years (and telling my students that they should contribute to open projects in order to get noticed), so I expected to disagree with the post, but that's proving hard. In order, the author's points are:
It's an arbitrary distinction.
There are smarter ways to spend your time.
Requiring open source contributions is sexist.
The first is moot, and the second is arguable, but the third hits home. Open source is overwhelmingly male: depending on how you count, only 1-2% of OS developers are women, compared to 12-15% in the industry as a whole . That means that if OS is your selection pool, in the long run you're going to drive the proportion of women in programming down.
My "solution" is to address the underlying imbalance by evening up gender ratios in open source, but (a) that's going to take a long time (particularly because so many men in open source still refuse to acknowledge that there's even a problem to address) and (b) even the way I've phrased it is a sign that I'm reluctant to admit the problem too. As another poster says elsewhere:
If you insist on a lot of experience in a particular male-dominated sub-culture as a prerequisite for a job, that reads as "we prefer [a subset of] men, basically, or at least people willing to work hard to minimise all the ways in which they aren't [part of the subset of] men" even if you didn't intend it to and even if you didn't want it to.
I hope that course projects like those in UCOSP will prove to be a workable middle ground, i.e., a place where young programmers can build their portfolios and reputations without having to worry that some crank is going to be allowed to sneer, bully, or troll without being held accountable. We hope to know soon whether we'll be able to run the program again this fall...
 The article's 28% is much higher than any number I've ever seen quoted elsewhere, and the source the article cites doesn't cite an original source itself.