You may have one blog and be satisfied with that. However, I am going to tell you why you about the SEO and other benefits of starting a second blog.

The first benefit of starting a second blog, is the experimental benefits. You get to experiment on do-follow versus no-follow and on various formats plus ad placements. You also get to try out different niches. There's also the mental benefit of allowing your mind to explore different topics and ideas.

Let's say your niche is about Ernest Borgnine. You can start an internet marketing blog chronicling your experiences on publicizing and monetizing your Ernest Borgnine blog. You can start a blog in vertical niches about other legendary actors like Rod Steiger, Robert Mitchum, Karen Black, etc. You can also start a guest posting/article directory blog where you can post articles linking to your own individual actor sites and allow people to post articles linking to their own actor sites.

Now, what is the Search Engine Optimization benefit of doing this? We all know that links from the same source tend to lose power over time(you can alleviate some of these effects by using unique anchor text each time and linking to unique pages each time). Now you can find new unique C-class IPs but by starting a new blog you can use old sources to get new link juice.

Then what you can do is link your new blog back to your old ones. Blog roll links are for less effective than creating new contextual links with varying anchor text. Using our actor blog links you can link your Rod Steiger page to your Karen Black page by stating that they both acted in The Player. You can link your Rod Steiger page to your Robert Mitchum page by stating that they both acted in The Longest Day.

Now what is the benefit of doing this versus just continuing to find new sources of links. Well, some sources of links are just better than others. Some places offer profit sharing. Some places you are just more familiar with and enjoy visiting more. With each new source of links comes new rules you have to learn and new interfaces to adapt to. There's also the benefit of interlinking within properties(this is a huge advantage of being 100% white hat). By returning to old sources you get link juice by everything being interlinked by your profile. You also get referral traffic from people visiting your profile and checking out your other pages.

If you haven't started a second blog then check it out and realize both the creative and SEO benefits.