In a way, I'd have to agree with Carl in that there are already too many things tied into a release of SQL Server. While I can understand the desire of Microsoft to bundle in all those additional features with SQL Server to add value for the customers, a full release of SQL Server should be more about changes to the RDBMS.

Remember that products like SQL Server, Oracle, DB2, and others are aimed at corporations. Most corporations tend to value stability more than the latest wiz-bang features. While the database vendors don't want their products to seem stale, corporate mentality and an "if it ain't broke don't fix it" attitude would make a new full release of a product consideration for new projects and systems. Upgrading the information infrastructure of an existing system is generally seen as a major undertaking. I know for a fact that some companies still run SQL 2000 for major systems and are only now just considering moving to SQL 2005.