If you look hard enough you can find several articles on the Internet which describe different ways to enhance SharePoint User Profiles with the Business Data Catalog. Each of the articles takes a different approach to implementing this functionality, however none of the articles provide a prescriptive step by step approach and end to end example. This article is geared toward someone who has limited or no experience with the BDC and provides a prescriptive step by step approach and sample code.
The other articles I found on the Internet about this topic include the following, they are well worth reading.
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