While I don't have any inside scoop on exactly why SQL Server 2008 is being delayed, I have been playing with recent Community Technology Previews (CTPs) and have noticed some significant compatibility issues between Visual Studio 2008 and SQL Server 2008. I suspect this at least part of the problem with SQL Server 2008, but there may be more issues.
What’s this mean? Well, among other things, don’t expect MCITP certifications on SQL Server 2008 until 2009. If you’re considering getting a MCITP certification on SQL Server, SQL Server 2005 is the product you should be pursuing.
And once you master the differences between SQL Server 2005 and SQL Server 2000, you'll find that SQL Server 2008 has only incremental differences.
Microsoft currently has three MCITP certifications for SQL Server 2005. They are:
And with Microsoft's Second Shot offer, it's much easier to get certified.
If you've been thinking about getting certified, now's the time to get a book, spend some study time, and take those exams.