The first one is 
Researchers at AAAS Annual Meeting Explore the Science of Kissing.
 The following quote gives you an idea of what it is all about: 
"Kissing, it turns out, unleashes chemicals that ease stress hormones in
 both sexes and encourage bonding in men, though not so much in women." I
 guess economists call this "interdependent utility functions." Meaning 
that what brings one person pleasure brings brings the other person 
pleasure, and vice-versa.
The other is 
Cocoa Prices Create Chocolate Dilemma.
 The article opens with "Soaring cocoa prices are creating a Valentine's
 Day dilemma for chocolate makers. They don't want to raise retail 
prices when recession-weary consumers are trying to limit their 
spending." The problem is crop diseases in Ivory Coast and Ghana. You 
might need to be a WSJ subscriber to read the whole article.
Here is a new article from yesterday's San Antonio Express-News (2-13-2011). 
Romance in bloom at workplace: Survey indicates 59% have taken the risk-filled leap.
 It seems like many people admit to having a romance at work and/or 
meeting their spouse at work. So what starts out as economic activity 
leads to some other needs being met.
Now the economic definition of romantic love.
 Abstract: "Romantic
 love is characterized by a preoccupation with a deliberately restricted
 set of perceived characteristics in the love object which are viewed as
 means to some ideal ends. In the process of selecting the 
set of perceived characteristics and the process of determining the 
ideal ends, there is also a systematic failure to assess the accuracy of
 the perceived characteristics and the feasibility of achieving the 
ideal ends given the selected set of means and other pre-existing ends.
The
 study of romantic love can provide insight into the general process of 
introducing novelty into a system of interacting variables. Novelty, 
however, is functional only in an open system characterized by 
uncertainty where the variables have not all been functionally looped 
and system slacks are readily available to accommodate new things. In a 
closed system where all the objective functions and variables must be 
compatible to achieve stability and viability, adjustments in the value 
of some variables through romantic idealization may be dysfunctional if 
they represent merely residual responses to the creative combination of 
the variables in the open sub-system."
The
 author was K. K. Fung of the Department of Economics, Memphis State 
University, Memphis. It was from a journal article in 1979. More info on
 it is at 
this link. The entire article, which is not too long, can be found at 
this link. 
Then there was this related article: 
Love really is blind, U.S. study finds. Here is an exerpt:
"Love really is blind, at least when it comes to looking at others, U.S. researchers reported on Tuesday.
College
 students who reported they were in love were less likely to take 
careful notice of other attractive men or women, the team at the 
University of California Los Angeles and dating Web site eHarmony found.
"Feeling
 love for your romantic partner appears to make everybody else less 
attractive, and the emotion appears to work in very specific ways in 
enabling you to push thoughts of that tempting other out of your mind," 
said Gian Gonzaga of eHarmony, whose study is published in the journal 
Evolution and Human Behavior.
"It's almost like love 
puts blinders on people," added Martie Haselton, an associate professor 
of psychology and communication studies at UCLA."
More links:
How to Be a Better Valentine, Through Economics by economist Paul Oyer.
Here’s what science says is the secret ingredient to making your love spark  
Can Giving Up Money And Material Things Lead To More Love? 
What Do Men In China Need To Get A Bride?
Adam Smith, Marriage Counselor
A Special Valentine's Message On Romantic Love
Can You Put A Price Tag On Love?
Do Opposites Attract? Not Usually, Except Maybe When It Comes To Money
Return of the Love Headhunters
eHarmony To Provide Personal Counselors To Help You Find Mr. Or Ms. Right 
Economist Paul Zak, aka Dr. Love (he studies the brain with "neuroeconomics")
This is your brain on love   (brain scans and biology seem to confirm the economic definition given above)
Dollars & Sex: The Blog of Marina Adshade