I am attaching a newer version of the txt file that incorporates all the review
comments.  Here are the only changes I am yet to make -

1) Refer to IanJ's virtual disk specification once it is checked-in.
2) Include information pertaining to drbd and other arbitrary block device
types.  This information can be included post 4.1 as I gather from the
discussion on this topic.

Please let me know if I neglected any of your comments or if you have further
comments.

Kamala