I know the current release in TechNet (which I am still fuming about MS's decision to kill off BTW) has sp1 integrated into it.

Alternatively, if you're looking at automating an install, have you looked at SQL Finebuild? I am currently researching it and it seems pretty intriguing. Additionally I think that Finebuild's creator is an SSC forum member.

SQL Server FineBuild[/url]