After upgrading your OpsMgr 2007 components and upgrading your SQL environment to SQL Server 2008, you will need to run some post installation steps. These post installation steps are only needed if you have done an upgrade from OpsMgr 2007 to OpsMgr 2007 R2. OpsMgr 2007 SP 1 had an issue with the localized text table continuing to grow. The main cause of this was converted MOM 2005 management packs running a lot of backwards-compatibility scripts, such as the converted Exchange 2007 management pack...(read more)

Read the complete post at http://scug.be/blogs/scom/archive/2009/09/14/cleaning-the-localizedtext-table-after-scom-upgrade-to-scom-2007-r2.aspx