An Argument for Emoticons

Make Any Conversation Creepier!
Image found via Google :) 

I use a lot of smileys. All the time. Sure, I hold back when I'm writing to someone I don't know and want to make it sound official, but most of the time, it's emoticon central. And I think that it should be okay.
Around 90% of communication (ish) is nonverbal. We've created these tools to help compensate for the loss of facial expressions over text communication such as instant messaging, texts, and emails. Consider the difference when you read...

Yeah.
Yeah :)
Yeah ;)
Yeah :(
Yeah -_-

I don't know about you, but I read those all differently -- something is lost without emoticons.
It's also a matter of efficiency. Why should I have to say, "This looks like a fun project and I'll get started right away," when I could say, "I'll start on this right away :)". Same point, more efficient. And business (and Generation X in general) is all about efficiency.
As a writer, I'm not saying you should depend on emoticons. If you have the time to effectively and efficiently convey your emotions and your tone through words, you should. However, I know that I hate receiving novel-length emails, and I especially dislike overly lengthy texts when a point could have been made in a few sentences.
I think we all know enough to avoid these shenanigans: "send pix of ur car!! :) :)" My mom texts like that sometimes, no joke. So aim for the happy medium -- emoticons can add meaning to conversations just like smiling while you're talking can.