After several months of passive membership I have begun playing with Twitter (see my Twitter feed in the right hand column, @alacre). Each year one social networking tool gets the full media spotlight and Twitter is the star of 2009 (Facebook was 2008 and Second Life was 2007). If the present media hype is any guide I'm probably one of the last people on earth to join up but you can't have an opinion unless you've actually tried using something.
The reason behind my hesitant approach is that once you start it's hard to set limits. My three blogs have become rather addictive and they're a bit like those wonderful Tamagotchi creatures that once inhabited people's cellphones; once you've got one you need to feed it regularly or it will die. I'm interested in following other people's tweets to get ideas and links but once you start following you soon feel the urge to start contributing! There are of course lots of tools that can gather all these channels together and I use Netvibes for all RSS feeds from news sites, blogs, Facebook, Twitter, Delicious and many other clever widgets. Another nice tool for gathering all your feeds in a graphically attractive way is Seesmic.
The key is to integrate all the new communication channels. Back in the early nineties there were numerous e-mail tools which were mostly incompatible with each other. It took a few years before the world could agree on common principles and suddenly we could all communicate. It seems we're heading into a similar situation today. As I write this I have the following communication tools open: desk phone, cellphone, 2 e-mail accounts, Skype, Facebook and Twitter. Then there are several more channels that I use only seldom. All with different user names, passwords, addresses and so on.