Share 'Do you twitter more to market yourself or for fun?'

Sometimes I wonder if I would be using Twitter if I didn't have a blog. I enjoy it and do get into some fun conversations, especially during "events", I use it mainly for marketing purposes. I just reviewed a great book on Twitter called Twitter Power http://connectwithyourteens.blogspot.com/2009/03/twitter-power-book-for-beginners.html which gives great insight into using twitter for marketing...