So, i was playing around with a question I saw on a Microsoft Forum and i took it a step further. The question related to ratings, tags, and MySites. But what got me thinking was if you can do Ratings on External Lists; as i am finding out more often than not, although Microsoft claims that External Lists are Lists like all others, they are infact not. In a previous post I determined that you are not able to use SPMetal to create a LINQ to SharePoint Class with connectivity to the List. I have also determined as you can discern from the image below that you are also not able to do Ratings. See below for prosperity.