This is a common question lately.  First, I strongly recommend you consider purchasing an addon that does this for you.  Build vs. buy is always touchy because sometimes it is easier just to write it than to get approval to purchase an addon...

I’ve been asked this a few times lately.  I typically point people to MSDN and give them a PowerPoint slide deck.  To make it easier, I’m posting this as my single link reference.  What's New for Microsoft Dynamics CRM 2011 (MSDN) @devkeydet