I have been thinking about this for a while now. Whether it's better to focus on one blog or two share your attention between two.I run this blog and SA Rocks. I think that the two are mutually beneficial but conflict one another on occasion. It's a difficult balance but one that I think has been extremely beneficial for me.What you need to maintain two (or more) blogsYou need a clear definition of each blogDiscipline is essentialCreativity is a mustFocusGoalsA plan - this is the most important on that I think I missed out on. You need to have a plan for each blog and each post that you write. If you don't have a plan the blogs can begin to cancel one another out and overrun one another.The prosCross populationCross referencingAssociation linksPost ideasCross-blog debatesAssociated traffic (gaining traffic from SA Rocks as the author)Cross-promotionThe consCross population - try to keep your blog posts separate unless there is a clear and present need for them to link.Time constraintsMental drainContradiction - I've struggled with SA Rocks to keep my positive outlook on SA Rocks and maintain it on my personal blog. This could be seen as a pro and a con as blogging on SA Rocks has allowed me to stay away from negative topics on my personal blog.I would love to find out how many other bloggers run more than one blog and if you do, what problems are you finding?