I believe an extension is needed for Live Clipboard.  Right now it only has the capability to copy & paste the information contained on the page it resides in.  In Ray Ozzie's example, all of the contact and calendar information is embedded on the example page itself.  However, there are two big problems with that:

1. The page itself will get real fat, real fast.  A contact could contain several addresses, several contact methods, links, and hey what about a blog feed?
2. The information contained in the page will get stale.  What if somebody changes the time of an event?  Somebody who has an old post cached in NewsGator might not know.

There's a simple solution to this, however.  The microformat needs to tell the clipboard what it contains, but not embed the information in the page itself.  (Or, if it does, it should be bare bones info, and only information that rarely if ever changes.)  Instead, the Microformat should tell the clipboard where to look for the master copy of the information--the URL where the fully fleshed out information can be obtained.  This solves both of the problems, and creates a kind of "object authority" where the master copy is always fresh and authoritative.

This will require some further refinement of the microformat specs (keep an eye on xFormats.org for details) to include the location of the full object spec, but certainly nothing that can't be easily overcome.