This is a six-month old article but I still enjoy it. What I have learned in my last two startups is that diversity is really important for success. Ultimately, your co-founders are the ones who would protect your proverbial back and the more that they bring to the table (that are not already on the table), the better. In fact, the less that you have in common initially with each other, the less baggage that you each would bring to the partnership. Over the years, I have learned painfully that in addition to learning to work with people who are different from you and would initially make you uncomfortable, we need to refrain from starting our company with family and friends. Starting a company together is the quickest way to destroy friendship. Starting a company with family (or hiring family into your company) is the surest way to alienate your business partners.
Sex and startups, two things in life that are best to pursue outside your gene pool.