Looks like the Operations Manager product team just announced that support for SQL 2008 R2 with System Center Operations Manager 2007 R2 databases:
I am pleased to announce support of SQL 2008 R2 with System Center Operations Manager 2007 R2 databases. Support is divide into two phase so please read KB2425714 for details.
Phase 1: Clean install of OM2007R2 on SQL 2008 R2.
Take a look at the KB to get OM2007R2 installed on a SQL 2008 R2 database server. In order to get the OM databases installed we had to go a different route from what's in the deployment guide so take a look at the KB.
Phase 2: Support upgrading SQL to SQL 2008 R2 with OM2007R2 already deployed.
Supporting this scenario will be coming as part of a future CU for R2. Stay tuned!
You can get all the details straight from the source here.
J.C. Hornbeck | System Center Knowledge Engineer
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