It seems that the 2.0.9 update RPM isn't showing up as mongo20*.
It's labeled as plain mongo-10gen-server - so you can't do a simple yum upgrade.
It looks like the pinned versions were overlooked, or it is not possible to pin to a specific branch.
- related to
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                    SERVER-9255 Previous 2.2.x stable version missing from RHEL CENTOS repositories -         
- Closed
 
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- 
                    SERVER-4808 Provide repo downloads of older versions of packages -         
- Closed
 
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