The recruiting industry being what it is, I'm sure that the future holds plentys of job opportunities for people who can invert binary trees on whiteboards. Or,

The recruiting industry being what it is, I'm sure that the future holds plentys of job opportunities for people who can invert binary trees on whiteboards. Or, on a more serious note, there will also be jobs for anyone with skills and experience in the field. The job market is good for developers. I'd recommend OSS and GitHub not as a prerequisite to landing a job, but as a means of adding direction to your career. At your day job you don't always get to pick the technologies and sometimes you drift into the backwater of old legacy code (which the companies, understandably, need to maintain). Doing OSS can be a way of getting your feet wet doing exciting stuff of choice, building experience for your next job and maybe even build a network. Doing fun stuff. That should be the main reason IMHO.