Question of the week: SQL Server performance

Oopps! Upgrade your browser pretty please.Oopps! Upgrade your browser pretty please.

The question is simple: is there any difference between the performance of the different service packs / editions of SQL Server? For example, is there a performance difference for the queries which run on SQL Server 2005 RTM, SP1, SP2 and SP3? If there is a difference, what is it and why? (There are some gold stars in stock now, so whoever gives the most detailed answer gets one! 🙂 )