The MSDN Solutions blog is not truly an AX blog, however you can filter the view to show just Dynamics AX related posts.  It is a nice quick way to keep updated from Microsoft, especially if you do not have access to PartnerSource or CustomerSource.  That will set it to view only things tagged with Dynamics AX.  Here is the RSS Feed for the filtered view.

MSDN Solutions Blog (AX Filtered)

Usefulness: 5

Design: 5

Return potential: 3
Rating: 13

The MS site is actually nice and clean.  The updates and provided links allow a visitor to quickly find the information they are looking for.  The only problem is that items are not posted very often for Dynamics AX.  However, unfiltered will provide more posts and there may be some general posts that can be helpful.

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