I just picked this up from Seth's Blog and watched the video he linked to. Watch it. Seriously. It is so important to know who you are and what you do and more importantly what you aren't. You must know where you stand and have the discipline and the courage to say no to what you are not. I'll say it again the discipline and courage to say no because there are going to be allot of bigger guys out there screaming at you to say yes.
I think this applies to everything in life. This just isn't business 101. This is life 101. It just so happens it is a good formula for running a profitable business.
Do you know what you are? Are you flavor of the day? Or are you passionately committed to what you believe in and what you are doing?