DR plan for Google Apps

[robin at digininja.org (Robin Wood)]

As I seem to be moving more and more into using Google Apps for a lot
of my life I was wondering about a DR plan in case anything happens.
I've found an interesting article on Lifehacker about various
techniques http://lifehacker.com/281635/back-up-your-google-apps-data
and a various other options but was wondering if anyone was using
anything like this and had any views before I go starting to implement
things that later turn out to be rubbish.

I'd be looking to back up mail and calendar but knowing about docs as
well would be useful in case I push those into Google as well.

I was also wondering about what to do if Google's mail servers go down
and my MX records end up dangling. My plan for this is to find another
service that will let me point an MX record at it and have it as the
lowest priority in the MX list, that way if Google does die then all
mail should end up in my backup location. Does this sound reasonable?

Robin