Out of the Box EP has the same functionality in WSS and MOSS.
For Role Centers, we do light up two role centers with MOSS specific components.If you have MOSS, the CEO role center and the SalesMarketingExecutive Role Center will use MOSS KPI List and Filter instead of equivalent functionality provided in the WSS  version of these rolw centers(by using SQL Reporting Services).

The end user benefit of using MOSS for these two role center is that
• In MOSS for these two role centers, you can change the filter at a page level ,where as in WSS you need to do it at the web part level.
• MOSS version uses KPI List to display the KPIs , so end user can easily personalize to add / change/modify KPIs. Whereas WSS uses SQL Report to display the same KPIs, so to change them you have to edit the report

The other advantage of using MOSS is that , you could use Excel Services or other BI components. But out of the box role centers does not use Excel services.Barring this the out of the box role centers behave the same way in WSS and MOSS.