In answer to your first question, yes, and it is very tough. On the two SharePoint 2010 rotations completed at the time of writing, as far as I know, nobody passed on the first time through.
I have written a short article about my experiences at http://www.spdoctor.net/Pages/article.aspx?name=SharePoint-2010-MCM. Many others have also blogged about it. But you will not find much detail in any of the blogs because we are all under NDA.
First you need to get through the interview, which is a challenge in itself, in order to get on the programme. And you will need the four SharePoint 2010 MCP exams.
The preparation is basically to work through the comprehensive pre-reading list, which is available at http://www.dynamicevents.com/upload/MCM-MCA/MCM/SharePoint/MCMSharePointPre-Reads.pdf. This contains scores of links to articles which themselves usually expand into numerous sub-pages. It took me weeks to work through all this. If you can get some practice setting up the more complex SharePoint environments this will help you prepare for the hands-on labs.