For as long as I can recall, one of the distinctions of being fluent in Chinese was that relatively few people in my environment were able to understand it. Of course, that's not to say that there weren't some great advantages accompanying the relative obscurity of a language--whenever, for example, I didn't want people listening in on phone conversations, I would simply switch to Chinese to fend off eavesdroppers. But imagine my surprise, then, especially in recent years to discover that increasing numbers of people of non-Chinese descent were capable of basic Mandarin. Many of these speakers were not simply educated through college courses, but were the products of years of assimilation in Chinese culture and language tutoring.
These speakers represent the growing population in the US that realizes the importance being multilingual. This trend certainly has its advantages; scientific research has indicated that children who learn multiple languages from an early age have an increased sense of creativity and improved critical thinking skills. Although bilingual children can sometimes confuse the varying grammar rules across languages, overall, polyglots have improved communication skills.
From a personal perspective, I've always believed in the importance of being multilingual because of the immense benefits that accompany language-learning. As a kid, I remember spending my summers in Shanghai and learning to speak nothing but Chinese for months at a time. Chinese was difficult to master but ultimately, provided me with greater memorization and reasoning abilities.
Overall, being a polyglot has major advantages in terms of gaining critical skills from language learning that are only now beginning to be recognized in society today. To end with a fun fact, the Broca's area, an area of the brain responsible for language, of polyglots is organized differently than those of monolinguists.