Couple of days ago, I started 2 identical Blog in the niche of Home and Mortgage. The first Blog hosted in Wordpress.com domain and the other one in private domain. The contentis pretty much same and they receive nice visitor from Google Search engine. But, after several months, the first blog that hosted in wordpress.com is received Google PR 4 and the private hosting only received PR1. After doing some analysis in https://siteexplorer.search.yahoo.com/, the Wordpress.com blog had several nice links from Botd.wordpress.com, so the PR is raised to PR4. But the private hosting is not get the good back link, Could anyone give suggestion some web ranking for increase the PR like botd.wordpress.com have?