We updated topics because the Windows SharePoint Services portion of the Cumulative Update fixes a pain point (possible data corruption and definite size limitation) in deleting, merging, and splitting content databases. From the Cumulative Update description, here's the problem, and how you can avoid it:
"If a site collection is very large, an attempt to delete the site collection from a Web application fails. This causes the stsadm -o mergecontentdbs command to fail when you try to move site collections from one content database to another. This issue is resolved by adding an optional -gradualdelete parameter to the stsadm -o deletesite command. If this parameter is present, SharePoint marks the site collection as deleted to prevent further access while a SharePoint Timer job gradually deletes the data in the site collection. After you install the hotfix package that this article describes, the stsadm -o mergecontentdbs command uses this gradual delete functionality by default."
Now that product team added the Site Collection: Delete timer job to run in the background and gradually delete anything marked as deleted, you can delete and move large site collections the way that you always wanted to!
Note: Although the Stsadm mergecontentdbs operation uses the gradual delete functionality by default after you install the hotfix, it's not the default for the Stsadm deletesite operation, so you'll need to remember specify the -gradualdelete parameter.
Here's the list of the topics that we changed as a result of the update:
Windows SharePoint Services topics
Office SharePoint Server topics