Data Access and Storage Home: Evolution of the SQL Server Programming Model from ADO to ADO.NET 2.0: "ADO (along with some made-to-measure tools like Remote Data Services) and ADO.NET are the two main data access technologies for SQL Server. Choosing one depends chiefly on the Windows platform you're targeting, Win32® and COM, or .NET. In addition to ADO and ADO.NET, and spanning the worlds of Win32 and the bright lights of .NET, is SQLXML, an object model that fully exploits the XML capabilities of SQL Server 2000.
In this article, I've discussed the main data access layers available to work with SQL Server. I've tried to put each into perspective to give the sense of the history, the current situation, and the future evolution.
In the end, ADO is the most reasonable (sometimes, unique) choice if you have to write COM, ASP, or Win32 applications. If you are instead writing an application to be based on the .NET Framework, then ADO.NET is a no-brainer. If you need to perform particular operations (e.g., server cursors, schema manipulation, bulk copy), ADO.NET might not offer the support you expect, but the trend is highly encouraging. ADO.NET 2.0, slated in Beta 1 in mid-2004, promises to integrate missing functions and facilities into the existing Framework, thus delivering a powerful, consistent, and self-sufficient data access layer."