Robert Manna recently posted some observations about the new Guide Grid feature that arrived with Revit 2011. It is intended to provide a bit more control over the view alignment between sheets. I complained about this process in an earlier post. It was only a month or so later that I saw a sneak peak of the Guide Grid concept.
It's probably simplistic of me to say so but it seems to me that it is an expansion of the existing Show Work Plane feature present for model views. I came to that conclusion because it shares the exasperating limitation of only allowing one dimension value to control the horizontal and vertical dimensions of the grid.
If you are interested in a little deeper commentary just read Robert's post. For now, if you use this new feature, just remember:
Don't DELETE a grid in the sheet view if you don't want to see it anymore. Set the Guide Grid value to none for the sheet or use Visibility/Graphics in the sheet view to turn it off.
If you delete a guide grid you'll remove it for all the sheets. You should get this warning though in an attempt by Revit to save you from yourself.
Align Views on Sheets
Aligning Views Between Sheets
Dept. of Wishes - Aligning Views on Sheets