Aside from making single people feel bad about themselves and ensuring that Hallmark, Chocolate Makers and Florists won't ever need to benefit from the government economic bailout program, I have rather mixed feelings about the holiday.
On one side of the coin, an excuse to express yourself to those around you is never a bad thing. But on the other, it's something you should be doing more than once a year.
That said, if I may make a suggestion in these troubled times:
Forget the flowers, forget the chocolates and don't even bother writing a card that will be read once; then discarded. Instead, look someone in the eye and tell them that you love them.
And then, do it every day thereafter.