I don't think that college is unnecessary. In fact, I'd say that as more and more people go to college, it becomes more necessary to hold a degree in order to compete--even at entry-level positions. I have friends that are getting beaten out for restaurant work because they don't have a degree (really).
This, to me, is where the problem lies. We are simultaneously overvaluing (for basic, entry-level work) and undervaluing (for higher-level jobs) college degrees.
There is no doubt that to get, say, an entry-level engineering job in today's market, you need a degree (and from what I've seen, preferably a Master's). But if you have your bachelors and are still struggling to get work that traditionally doesn't require one (administrative assistants, call center employees, service industry staff, etc. come to mind), is it worth spending $40-$200k on a degree?
Furthermore, skilled trades in the United States are plummeting. Mike Rowe addressed this very well in his TED talk[1]: electricians, plumbers and mechanics are getting more and more rare (and are still highly in demand) because of the stigma of not attending college.
I believe that in the next several years, as unemployment for college graduates becomes more visible, that skilled trades will once again become respectable, admired careers. It's crazy to me that people like Master Electricians ever became stigmatized at all--we are in serious need of their services, and it requires immense skill and intelligence to perform their jobs.
1: http://www.ted.com/talks/mike_rowe_celebrates_dirty_jobs.htm...