Reading around the net today, I came across this new article recently posted on MSDN (http://msdn.microsoft.com/asp.net/default.aspx?pull=/library/en-us/dnaspp/html/CustEntCls.asp). As one of the original members of MSDN I keep my eye on how they are doing from time to time. Let me just say that the schlock these guys are peddling these days is terrible.
This article on Custom Entity Classes is the most ridiculous offering I've seen yet. Talk about promoting technology for technology sake. Custom Entity Classes have all the disadvantages of O/R mappers, none of the benefits of JIT mapping, spreads DA logic around instead of centralizing it, and is just plain WRONG. If you want a DAL that is purely schema reflective, use a dataset or dataview and save some code! You gain nothing by pushing schema further into the user base. There is already a perfectly good abstraction layer at the stored procedure level, why add a second or third level? This doesn't even make good common sense. Adding special operations to the DAL is completely contrary to Service Oriented Architecture (SOA) and almost every reliable design pattern ever.
In reality this is a good introduction to Custom Entity Classes which are just another form of O/R mapping that is worse that JIT mapping and only paves the way for the lazy to slide into the realm of custom business objects that tie data and operations together. Tying data and operations is the #1 most detrimental flaw in practice today. It inhibits interop, hinders maintainability, and increases complexity. Yet here we are, encouraging people to learn how to practice chaotic, undisciplined coding patterns. I'm thoroughly disgusted at this obvious sell-out.
Maybe if the author had read some of the references and actually built and maintained a few real applications he wouldn't be so quick to sell this drivel.