No, just the menu option. Switch to outline view, and you will see the
icon for Master Document view at the right end of the outlining toolbar,
I think.
I assume you know that master documents are not reliable--they may
behave better in .docx format, but I don't know that anyone has tested
them in Word 2008:
http://www.mvps.org/word/FAQs/General/WhyMasterDocsCorrupt.htm
(hit reload a few times if you get a blank page)
