I know, I know, in time these people will own a private medical practice, receive tenure at their university, or what have you, and they deserve encouragement in the meantime. But immediately bestowing upon them all the positive connotations of the term "professional" when they are pretty clueless and powerless as far as career life is concerned, only serves to inflate their egos, already bloated from having attended elite colleges. Any ranking of desirable cities for young, aspiring people should then reflect this: which cities score highest on the "deluded sense of self-importance" factor? While there's plenty to be said in favor of emphasizing easily measured factors like cost-of-living, number of historical landmarks per square mile, and so on, the factors that try to get a hold of the more subjective aspects of city life should focus on how easy it will be to get along with your peers vs. wanting to throttle them after a one-minute chat.
A city is only as enjoyable as the people who live in it. Anyone who has traveled to or lived abroad in cities with great architecture and a cornucopia of nightclubs and bars -- but where the 20- and 30-somethings are more likely to be mature and humble, as opposed to eternal bratty adolescents -- knows how frustrating it is to return to the US, where the best cities ranked by non-human measures are far more likely than their Continental European counterparts to be peopled by boors, jerks, skanks, and bottom-feeders.
Curiously, one of the handful of factors that the Forbes ranking considered is, well you read it:
Of course, even the most driven young professionals need to let off steam. With that in mind, the final metric was measured which cities had the highest share of never-married people in their 20s and 30s. Never married is an important qualifier. For example, of the 40 largest cities, Salt Lake City has the third-highest population share of people ages 25 to 34, but its standing as No. 27 in the never-married category really puts a damper on the nightlife.
I would be in favor if the factor were "never-married people 25 or younger," but for this measurement to take into account people in their 20s and 30s gives you quite a different picture from simply "good nightlife" -- it's more of an indication of how immature, self-absorbed, and off-putting the people are. If you have never been married, well into your 30s, you either have no interest in long-term relationships (meaning longer than a few years), you have an interest but are too wrapped up in your career to follow through, or something about you makes you unmarriageable. I'll admit there are sympathetic exceptions, but let's get real. For instance, droves of IT geeks who flock to a high-tech Mecca will surely ramp up its coolness factor by inflating the "never-married" statistic.
At some point in your life, you have to grow up -- or else face the consequences that the Boomers do (and perhaps half of Generation X -- they're more heterogeneous in this respect).* Fundamentally, growing up is about more than just having a job or even doing it well -- all but the unemployed will have a job, and students at elite colleges excel at what they do, so something else is needed to tell "the boys from the men." That prevents any criteria which are almost exclusively a function of earning an income: having your own apartment or house, shopping for groceries, paying taxes, etc.
Before the revolution of the youth in the late '60s and early '70s, these milestones probably correlated strongly with the true markers of maturity, which have more to do with one's character and behavior. Now, however, they have become uncoupled, and not a few 30-somethings resemble Tom Hanks' character in Big in their behavior, attire, and the appearance of their house / apartment. Because of the stronger, more deeply rooted social traditions of Continental Europe, the 1968 youthquake did not fundamentally alter society the way it did here: it was like a spring that someone stretched out but that quickly snapped back to a resting state. Our spring is more elastic and has yet to return to where it feels comfortable.
That presents some trouble for recent college graduates who are enthusiastic about moving to one of the top 10 cities in the Forbes ranking: it may be fun for a few years, but if there aren't larger social pressures that will push you toward adulthood, it's easy to get stuck in your early 20's. Now, if you could freeze everything else inside and outside of you, that would be rather tempting -- but in reality, you're not getting any younger, and becoming a mummified teenager is not flattering for anyone.
* It's a cop-out to suggest that growing up per se stifles one's creativity and sense of wonder -- for one thing, most people are not particularly creative or curious at all. Those who are creative but seemingly immature, for example the mathematician Paul Erdos, are more aptly described as "child-like" than "adolescent." Adolescence, you'll recall, is the time in your life when you're too busy thinking about sex to get much accomplished creatively, and when you affect an air of sophistication, losing interest in children's fantasies. In a documentary on Erdos, N is a Number, those who know him well liken him to a child, he professes a fascination with children, and he confesses that he receives no pleasure from sexual thoughts.