Well, BULLSHIT! It's all in the math!
According to an article published in USA Weekend magazine in 2003 (there are more recent ones, I just liked that one!) attractive faces are those which are more symmetrical and have a certain ratio (1:1.618) which recurs in beautiful things.
"...beauty is simply balance: The more symmetrical a face, the more appealing it appears. "
And not only that, beautiful people tend to be more succesful, get more attention and smell better (???). The same article refers to another research which compares attractiveness to a mask created with the above-mentioned ratio.
Welllllllllllll.....how's that for a good take at the mirror?
In terms of symmetry, nature has been kinda scatter-brained with me (what's with the single dimple?) so I'd still rather think that the idea of beauty IS subjective.
And somehow after reading all this, all I can think of is "There are things money can't buy, for everything else, there's MASTERCARD!" :P