Golden Dysprosium
Ugh. That was a weird article.
Erm, as for the explaination, it seems these "ages" are determined by the "rotation" of the constellations. I was born in July, so I'm a Cancer (no jokes, please), meaning I was "born under that sign". It's sorta the same thing, except instead of months, it's 1,000s of years. It kinda makes sense, since they used the stars for navigation and such. The significance of these 'ages' is that they're supposed to bring change, and usher in a new era. Apparently, the next one is going to be like the 70's, with lots of hippie/fight-the-power crap and the like. The 2012 thing predicts the world will end, but the Mayan calendar was apparently made backwards (meaning, they picked a day waaaay in the future, and worked back). It's only when their calendar ends. If you aren't worried about the earth exploding by Dec. 31, 2009, I wouldn't worry about this 2012 thing.
It's fair to note, though, that astrology - even if it were grounded in science - is completely unreliable by virtue of an expanding universe. Our little dustball doesn't make neat, perfect rotations each year. Since the time the constellations, namely your sun sign, rising sign, moon sign, etc., were determined, the stars have shifted. So much so that the entire system is nearly one sign off at all times.
As for the Age itself, even foremost astrologers can't agree on the date of its onset, giving approximations that vary within three thousand years of each other. They can't even agree on what it means, citing the development of every "Aquarian" advancement under the sun, from computers to culture.
The influence came in pop culture through use of the notion in the 60s and 70s. And that's what the Age of Aquarius is, really; hippie pop culture. It's a nice idea, but to take it seriously is an unbelievable fallacy.
I wouldn't worry about it. This movie coming out is about as grounded in legitimate research as I'm grounded in potting soil.