Today i visited the Stefan Gobner blog and found very good info.
The KB articles for April CU can be found at the following locations (they should be available in a couple of days):
Reference Source Link- KB 2598130 - WSS 3.0
- KB 2598129 - MOSS 2007
- KB 2598321 - SharePoint Foundation 2010
- KB 2598151 - SharePoint Server 2010
- KB 2598152 - SharePoint Server 2010 with Project Server
As you see there is a separate Full Server Package for SharePoint Server 2010 with Project Server which simplifies patching of this common installation.
The Full Server Packages for April 2012 CU are available through the following links:
- Download WSS 3.0 April 2012 CU
- Download MOSS 2007 April 2012 CU
- Download SharePoint Foundation 2010 April 2012 CU
- Download SharePoint Server 2010 April 2012 CU
- Download SharePoint Server 2010 with Project Server April 2012 CU
After installing the fixes you need to run the SharePoint Products Configuration Wizard on each machine in the farm.