SQL Server 2008 Express installs SQL Agent (but don't bother trying to start it)
If you have installed either of the Express Editions available in the SQL Server 2008 RC0 download you may have noticed that as well as the SQL Server service for the Express instance, setup also installs the SQL Agent service. Great news you might think but no, the service is installed in a disabled state and will error if you try and start it manually. This is a change in behaviour from SQL 2005 Express Edition which did not create the SQL Agent service (or even include sqlagent.exe) and is far from ideal and may be comfusing to customers as confirmed by Microsoft in my Connect Bug for this issue however it also won't be fixed in SQL 2008.
Why do I care (a) because I think its confusing for customers and (b) because I maintain the SQL 2005 Service Manager tool on Codeplex which despite its name does support SQL 2008 and this makes my life more difficult because I now have to check the instance editions and filter out SQL agent for 2008 Express instances (so for totally selfish reasons then!). Along with the reappearance of the FTS service under a new name in RC0 it's making adding SQL 2008 compatability more painful than I had hoped :-)