It's almost impossible to attend a meeting that doesn't have a speaker with presentation on social media. They all swear by it. If it's up to them we have to twitter as much as possible, create as lots online profiles and tell everyone every second what we are doing. 
As always the response is the same:
'How does this social media-thing work?'
'Do I have to publish ten times?'
'That takes much time, I'm way too busy for this.
Besides, what do I tell people?'
If I had a dime for every time they...
Still, reality is that you can't go around social media anymore. If you don't use it, you are the exception. Not them. Luckily you can make it yourself lots easier when you start using social media.
So don't create profiles everywhere, but start thinking first. Who do you want to target? What social media do they use? That's where you need to be. For example, if it is managers and directors you go to LinkedIn.
Also think about what you want to tell through social media, because we already know the line '...met interesting people last night'. Be creative and make sure your content adds value.
Oh, and if your target uses multiple social media, then don't go to each one one of them. Use a program like Tweetdeck. This allows you to type your message only once and sends it away to different social media. When I send a message in Tweetdeck, it appears on Twitter, Facebook, LinkedIn, Hyves and Google Buzz. Yes, it can be that easy.