i have done the upgrade for my Sharepoint 2007 to sharepoint 2010 by Database upgrade.
and i am facing only one problem with the IT team workspace template site which is as follows
[STSADM] [SPContentDatabaseSequence] [WARNING] [10/21/2010 10:31:22 AM]: WebPart class [1f221ac3-a0fb-7f40-62ac-4d83b23d41c2] is referenced  times in the database [WSS_Content_database], but is not installed on the current farm. Please install any feature/solution
which contains this web part.
[STSADM] [SPSiteWssSequence2] [INFO] [10/21/2010 10:47:12 AM]: SPSite Url=http://ex.domainname.com/division/IT
[STSADM] [SPSiteWssSequence2] [WARNING] [10/21/2010 10:47:12 AM]: Feature could not be upgraded. Exception: Feature definition id '75a0fea7-c285-4c09-839e-0b5e1453e387' could not be found.