[SharePoint Conference 2011]
Here are a few interesting items from Sam Hassani and Chris Whitehead's session "How to Effectively Deploy Updates in SharePoint 2010".
Update version numbers
If you want to find out if a particular patch is contained within a cumulative update (CU), you can dismantle the CU and check if the version number is higher than the version number of the patch in question. If the CU version number is lower than the patch version number it does not necessarily mean that the CU won't include the patch. However, if the version number of the CU is higher than the patch number then it will definitely include the patch. More information on how to dismantle a CU and check the version number in this whitepaper.
New in SharePoint 2010 you can update binaries on SharePoint servers before upgrading the content databases. With backwards compatibility, you can reduce downtime when installing SharePoint updates by first installing the new binaries on the servers in your farm without taking the farm down, and then taking the farm down only for content database upgrades. More information on backwards compatibility here.
Multiple threading database attach
To further speed up the upgrade process, you can detach the content databases from your farm prior to updating the binaries, and then re-attach multiple content databases for upgrade in parallel. To attach multiple content databases at the same time, use multiple instances of PowerShell with the Mount-SPContentDatabase and Upgrade-SPContentDatabase commands. More information on multiple thread database attach here.
Office Server update package contents
As of August 31, 2011, you will only have to install one package for your SharePoint Server 2010 and Project Server 2010 implementations as opposed to installing the SharePoint Foundation 2010 updates from another package. The Project CU's will contain all the bits for Project, SharePoint Server and SharePoint Foundation. The SharePoint Server CU's will contain the bits for SharePoint Server and SharePoint Foundation. More information on the packaging of Cumulative Updates is available here.
Cumulative Updates for Language Packs
Any updates for language packs are included in the regularly released CU's. However, service packs for language packs are not included in SharePoint service packs. So the only time you should have to do any separate patching for your language packs is when you're installing service packs.