[VS2010] What is the.Net Framework 4 Platform Update 1 and how it integrates into Visual Studio 2010?

Hi all, After the Service Pack 1 for Visual Studio 2010 April 18 has launched the Net Framework 4 Platform Update 1, and some will probably ask what is this update? Personally between service packs, hot fixs, patches, etc. I I lose and now comes a new type of distribucíón for special cases: "platform update". [...]