I just want you to know that my name is Kimberly. It is my given and professional name. I have not gone by 'Kim' since around 1997. Once I started college, I changed my name. So, that's, what? THIRTEEN years as 'Kimberly'. Look, I'm not sure if you're too lazy to type/say the whole thing, or if you just don't care, but damn it, *I* do care. It annoys the ever living shit right out of me. It is presumptuous of you to assume that I go by Kim when nothing (my email, my ID, my student ID, credit cards, etc) says, "Kim".
The most common thing I hear is, "I have a friend, cousin, mom, grandmother, sister-wife named 'Kim'." Fabulous. We all know "Kims", I get it. But if I introduce myself as "Kimberly" don't immediately think it's up to you to shorten it for me. I realize that we live in this technological age where we need faster and faster ways to communicate, but soon, I'm just going to be "K" because you lazy motherfuckers can't be bothered to say the whole damn name. Sometimes in emails I'll type KimBERLY, but that usually doesn't get the point across either. So, I've had to resort to a standard, "I prefer my given name over the abbreviated version of my name". I swear, though, I'm seriously considering making it part of my professional email signature.
Now, there are special caveats. My parents, my family (who for 18 years called me 'Kim'), some high school friends (but even they have switched over), and my doctor who is so sweet and kind that it doesn't bother me to have her shorten my name. It's endearing, and I've never corrected her.
But as for the rest of you name-shortening jackwagons, this is your warning. Because throat punching is my next recourse.
PS. STFU about me shortening my son's name to 'Lex'. If you had our last name, you'd shorten your kid's name so that he had a snowball's chance in hell in learning to write it too.