If you want to compare what feature comes with the different editions of SharePoint 2010 you can go to this site: 
You will find a nice table that compares SharePoint Foundation VS SharePoint Server Standard and Enterprise. 
Be aware that under the Enterprise edition it says that you have access to these features:
Advanced Content Processing
Advanced Sorting
Business Intelligence Indexing Connector
Contextual Search
Deep Refinement
Extensible Search Platform
Extreme Scale Search
Rich Web Indexing
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They are in fact available with the Enterprise version of SharePoint Server 2010, but you need to have a Fast Server in order to use them.