We don't use online help from within VS, nor do we allow it. All help system files must be loaded locally on the developer's system. With that being said, it is impossible to use the help system within VS 2010 if you are doing any kind of web development or any of the other types of development that make up the 90% of the library that is missing.
When will the full MSDN Library be available for offline use?
For more information, you can visit my blog post at: