The new cumulative updates for SharePoint Server 2010 and SharePoint foundation 2010 are ready to download:
MSF2010:
KB 2459125 Full server package for Microsoft SharePoint Foundation 2010
Download: http://support.microsoft.com/hotfix/KBHotfix.aspx?kbnum=2459125&kbln=en-us
SPS2010:
KB 2459257 Full server package for SharePoint Server 2010
Download: http://support.microsoft.com/hotfix/KBHotfix.aspx?kbnum=2459257&kbln=en-us
Project Server 2010 December CU:
http://blogs.technet.com/b/projectadministration/archive/2010/12/15/microsoft-project-server-and-sharepoint-2007-and-2010-december-cu-2010-are-mostly-live.aspx
Further instructions and information:
After installing the packages, you may be prompted for a reboot of your Server! Please don’t forget to run the PSConfig Wizard anyway, even after reboot just to ensure that all updates has been applied completely and successful!
As usual, you can use the command line on each server in Farm: “psconfig –cmd upgrade –inplace b2b -wait”
A complete list of all published updates since Beta/RTM is found here: 2010 cube sheet
Known Issues (regressions in Dec.CU):
Problem 1:
“You cannot create an AD DS synchronization connection … after Dec.CU 2010 installed (KB 2490381)”
In some cases the given workaround may not help or no AD-connection at all can be created.
If so, try to recreate your UPA, do a reboot and then recreate your AD-connection.
Problem 2:
“You cannot create an Active Directory sync connection when the NetBiosDomainNamesEnabled property is set to true“.
It fails with “Unable to process create message” error.
Workarounds:
For Problem 1: see KB 2490381
For Problem 2: see KB 2519279 -> no known workaround available yet.
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Solution:
Both of these issues have been verified as resolved in the February 2011 CU for SharePoint 2010.
SharePoint mysteries and more... 
Steve,
Thanks for the great information. I have a question regarding an in-place upgrade to 2010.
Do you need to install SharePoint Server 2010 Cumulative Update Server Hotfix Package (MOSS server-package): December 31, 2010 BEFORE you provision and configure the UPS or is it reccomended to complete the setup of UPS using the base 2010 upgrade and then apply the CU?
I am not using the Farm Configuration Wizard (FCW) and will be doing this manually.
Thanks,
Joe
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Hi Joe,
Regarding the Dec.2010 CU, you should first install the update and after that provision the UPA services. Along with all other updates that are addressing many issues all around User Profile Services, most of these fixes are only working once the UPA has been new created.
Therefore: Yes, I'd recommend always if possible, first to apply the udpates and afterwards ccreating and configuring the UPA stuff 😉
Note!
Currently we noticed a regression with the Dec.2010 CU as described here:
You cannot create an AD DS synchronization connection … after Dec.CU 2010 installed… (KB 2490381)
HtH,
greets, Steve
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