An interesting article on News.com.au ...

Kisses can seal a couple's fate

Women use first kiss to gauge compatibility
Good kiss means partner is worth preserving
Bad kiss means no invite for coffee

IT is a moment of high anxiety in any romantic relationship. But now researchers have found that the first kiss may be even more important than anyone suspected.
While a kiss may just be a kiss for a man, for a woman it is an all-important means of gauging a prospective partner's compatibility. She uses it, the study suggests, to assess a "rich and complex exchange" of romantic and chemical clues that pass between partners as their lips touch.

A "good kiss" will help convince her that the partner is worth persevering with but a man who is judged to be a bad kisser is unlikely to find himself invited in for coffee.
In the longer term, the woman treats kissing as a means to induce bonding and assess whether her partner has remained faithful and interested.

For men the kiss is much less important. It might be a source of hormonal information but it's mostly seen as a preliminary to sex. A man tends to regard a good kiss as one in which he's allowed to use his tongue and is rewarded with moans of pleasure, the study found.
"The information conveyed by a kiss can have profound consequences for romantic relationships, and can even be a major factor in ending one," Gordon Gallup, of the University at Albany in the US, said. "While many forces lead two people to connect romantically, the kiss - particularly the first one - can be a deal-breaker."

The study, published in the online journal Evolutionary Psychology, suggests that clues to a person's health are passed on by kissing. These clues are picked up and understood - consciously or unconsciously - by the kissers but are more important to the female because she is more interested in a long-term relationship.

Women were more likely than men to take into account the smell of their partner's breath, the taste of their mouth and the state of their teeth during a kiss.

Women were less than half as likely to have sex with a man without first enjoying a kiss, and less likely to tolerate tongues on a first date. Men were much more likely both to continue to want sex even with a bad kisser or without bothering with a kiss. Once a relationship was established, the researchers found, men grew less interested in kissing whereas women continued to give kisses a high priority. They were more likely to kiss a partner after sex than men were.

Researchers from three US universities surveyed 1041 college students, most aged 18 to 25.
The Times, London, in The Australian

So, there you are, the secret to kisses. Sometimes I wonder how people come up with interesting insights like this. But I suppose being a woman I agree with the fact that our species make a bigger deal of a kiss than a man does. The man is usually the first to initiate a kiss at the beginning of a relationship but it is always the woman who continues to be interested. Kissing is a very intimate act, a kiss means he cares, it means he wants you. Your first kiss will forever be etched on your mind, and it is this first kiss that always brings back the nostalgic feeling, of being loved, being wanted. Every time I remember our first kiss, it never fails to create that warm fuzzy feeling - and it always brings a smile to my face.