I've kissed a lot of girls in my life. My first kiss was two months before my 16th birthday (for shame) and it was amazing. I kissed as many girls as I could before my two year mission (had to fill my canteen, you know?) and then I did my best to get back into my snoggin' groove as fast as I could after I got home.
I had a conversation with a non-member lady friend of mine the other day. She was baffled at how Mormon guys could be so interested in making out. It was hard to explain and I talked in circles for a little bit until I figured out exactly what I was trying to say, but here it is... in a nutshell (and I apologize for the stereotypes):
In non-LDS relationships, I'm pretty sure that the goal of the guy is to have intercourse with the girl. Good old-fashioned sex. The girls usually know what the guy is trying to do, so she doesn't do anything sexual, really, until she's ready to go all the way. Non-LDS girls don't want to be involved in horizontal make-outs on the first date cause they know what will probably end up happening... intercourse. Clothes will start coming off and stuff. So, the girls don't participate in that sort of activity because of where it will (most likely) end up.
In LDS relationships, the girl pretty much knows that the RM she's going out with won't try to have sex with her. Since she's pretty sure she won't be pressured to do anything she's not comfortable with, she's much more likely to participate in vigorous, lengthy, horizontal, uninterrupted, gentle, face-caressing, passionate kissing.
Non-Mormons keep a tally of the girls they sleep with. We (Mormons) keep a tally of the girls we make-out with. We can't even keep a tally of light or heavy petting. As soon as we start keeping track of that stuff, people might think we're competing with each other... or maybe that we're TRYING to go that far with girls... and we totally aren't. Sometimes it just happens. But when it does, I assure you, the only thing we write down on our list of accomplishments is the fact that we made out with her... not the other dirty stuff.
For example, I will almost always date someone until we snog a few times. It's not like I only date her so I can make out with her. Usually, I'm genuinely interested in her until we snog. After we've made out a few times, I realize that I was only interested in her for "the chase". Once I've caught her and we've made out, I'm done.
From what I understand, something similar happens in non-LDS relationships... only that feeling of "I'm done" doesn't happen until the couple has gone all the way.
I hope that clears things up a bit.