Last night, Sam and I went to the New Hampshire .Net User Group to hear Larry Kim speak about XML Schema and other topics concerning Advanced XML Data Modeling.
Afterward, we had an opportunity to talk with Larry. He works as a technical director at Altova (XMLSpy is their premier product). For his presentation, Larry used the soon-to-be-released version of XMLSpy 2004.
Larry is a remarkable guy, having written four (4) books in the last 2-3 years. His latest is The Official XMLSPY Handbook:
From what I understand, the book provides a 90-day evaluation CD version of XMLSpy 5 Enterprise Edition (that's 60 days longer than the version you download).