I have both Microsoft Office 2004 and 2008 installed on my machine for compatibility reasons. However, both versions of the application show as, for example, Microsoft Word in the menu bar when running. I wanted to change this, and found an easy way to do so. This only works for the Office 2008 apps, not for the Carbon Office 2004 apps (as you can't drill down into their packages). There may be another way to change those, but I only needed to change one of the two to be different, so it's OK for my purposes.
In Finder, Control-click on the application bundle (i.e. Microsoft Word), and select Show Package Contents from the pop-up menu. Drill down to Contents » Resources » en.lproj (or English.lproj as some apps may use, or whatever is appropriate for your language). Control-click on InfoPlist.strings and use the contextual menu to open it in TextWrangler, BBEdit, or TextEdit.
At the very bottom of the file, change both the keys for the display name you want. For example, for Word, I used:
CFBundleDisplayName = "Word 2008"; CFBundleName = "Word 2008";This changes both the menu bar name and the name that shows up in the Finder's Open With menu, and other places. Hope this helps someone out.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20091113094131870