Thanks for the info on nofollow and pagerank. It makes sense that this will always be a moving target less everyone will eventually game the system until it’s worthless but at the same time it’s worth it to know a few tricks. I still have open concerns on how freshness of content factor in, the only time i’m ever annoyed by search results these days is when the only links available (on the first page at least) are articles from 4 years ago.
I was exactly thinking the same thing what Danny Sullivan had said. If comments (even with nofollow) directly affect the outgoing PR distribution, people will tend to allow less comments (maybe usage of iframes even). Is he right? Maybe, Google should develop a new tag as well something like rel=”commented” to inform spiders about it to give less value and wordpress should be installed default with this attribute 🙂
The SEO starter guide describes much of what your SEO will do for you. Although you don't need to know this guide well yourself if you're hiring a professional to do the work for you, it is useful to be familiar with these techniques, so that you can be aware if an SEO wants to use a technique that is not recommended or, worse, strongly discouraged.
A breadcrumb is a row of internal links at the top or bottom of the page that allows visitors to quickly navigate back to a previous section or the root page. Many breadcrumbs have the most general page (usually the root page) as the first, leftmost link and list the more specific sections out to the right. We recommend using breadcrumb structured data markup28 when showing breadcrumbs.

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