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I am pretty sure the SEOmoz toolbar uses the same metrics as Open Site Explorer, which is only updated a few times per month. In any case, creating a new page means you are starting off with little or no authority PA:1; however, once you include 301 redirects to that page, internal linking structure, and links from external websites, that authority will grow. As for your other page being at the same Google position as before, that is good; however, that is not always the case. You are correct in stating that a 301 helps transfer the link juice from one page to another, but it is not a 1:1 transfer... which means that in some cases you could lose traction in your current Google position. All of that being said, it sounds like you have everything set up correctly with your 301 sending link juice and traffic from your old page to your new page. It will take a couple weeks (typically) for SEOmoz to update Open Site Explorer and the SEOmoz toolbar to reflect these changes. Also, it can take some time for Google to rank your new page accordingly, as it must built some trust and authority with Google. Hope this helps. Mike