I think the critical part of all this is: know yourself. Most of us know what we are good at and what we are NOT good at.

Personally I hate accounting. I understand numbers, and when forced at gunpoint I will do accounting - but I prefer to get some sharp cookie like Evan working with me on the numbers side. That is why I force myself to do the numbers before I do any new business venture - just because I know it's the part I hate the most and I'm probably not going to give it the attention it deserves unless I attempt to do the numbers myself. Then after I think I have them right I have the sharp cookie review them for me and tell me what I've missed.