A few friends recently have asked which platform they should use to start a blog.  Invariably the decision comes down to WordPress or Tumblr.  Currently I am using WordPress that I have hosted at Dreamhost.  I have used both blogging platforms extensively and have observed some really big differences in each platform’s ability to help you get visitors.  Here are some observations I have made using my own blogs’ data and from data we have internally at AddThis.

• According to Google Analytics, my Tumblr blog has no Search Engine Optimization (SEO) juice.  I have almost zero referrers from a search engine.  This means the only way Tumblr gets me new visitors is from social traffic or people manually typing in my address.  WordPress does a great job with SEO, and with the All in One SEO Pack making sure my posts are crawl-able is very easy.
• Visitors are more likely to share from WordPress blogs than they are from Tumblr.  WordPress’s platform is easier to customize where the sharing buttons appear on each post increasing the likelihood to share.  Shameless Plug:  AddThis supports both WordPress and Tumblr and we give you tips on how to get the most out of sharing with each platform.
• When sharing from Tumblr does occur, it delivers social traffic, and in one specific case it delivers a knockout.  When I see someone share my Tumblr blog post to StumbleUpon, it is amazing to see how much traffic that arrives on my site from StumbleUpon.  A single share drives on average, 500 views, which is amazing.  On WordPress a single share to StumbleUpon drives 3 views on average.  I have asked people at StumbleUpon and Tumblr why that may be and neither company could explain it.