We have released the Payroll 941 form changes for 2012.  There are no calculation changes, only form layout changes.
If you do not print our actual form and line it up with a form in the printer, you should be fine by not installing this update.
It will be up to you if you want to install it based on your environment.

Link to the form layout from IRS and instructions:
http://www.irs.gov/pub/irs-pdf/f941.pdf

Below are the details of the changes, this will be a CODE update/msp install that needs to go on each machine if you choose to install this update.
Lines 6a, 6b, 6c: These were “Reserved for future use.” These have now been removed
Line 6e: Total taxes before adjustments – is now renumbered to 6.
Lines 6-10: need to be moved up
Lines 10 & 11: there needs to be a space between them
Lines 12a – 15: need to be moved up
Line 17 has been renumbered to 16
Line 17: all checkboxes and Tax liability month boxes  need to move up

There is no manual as no tax changes were reported, just a new 941 form. 
Unfortunately, the “form” is in the code so we could not export this out as a packaged report for you to install.
If you still print the actual form on a pre-printed form and need these alignment changes, then you need to install the update.

Version 10.0 after the install 10.0.1841 
Version 2010 after the install 11.0.1935

Now Available 941 form changes - Payroll Tax Update for Microsoft Dynamics GP 10.0
https://mbs.microsoft.com/customersource/downloads/taxupdates/usgptu10.htm?printpage=false
https://mbs.microsoft.com/partnersource/downloads/taxupdates/usgptu10.htm?printpage=false
  
Now Available 941 form changes -U.S. Payroll Tax Update for Microsoft Dynamics GP 2010
https://mbs.microsoft.com/customersource/downloads/taxupdates/tugp2010.htm?printpage=false
https://mbs.microsoft.com/partnersource/downloads/taxupdates/tugp2010.htm?printpage=false

Good luck with your quarter-end reporting!

Terry