Since we work on ALL flavors of MS SQL from 6.5 on up, the question is always out there - "why upgrade to a newer version?"  Note that although we are a Microsoft Partner, we prefer to take a look at their products from an Programming/End-User perspective.  SQL Server Central just popped out an nice simple article on the main reasons to upgrade (http://www.sqlservercentral.com/columnists/sjones/2988.asp) for an existing installation.  Note that there are MANY more improvements that are NOT listed in the article, but these are many of the main reasons for an upgrade (vs. an entirely new DB/front-end that can take advantage of the newer functionality without necessitating a whole re-write).