Ten years ago, when Microsoft decided to jump into the XML train, I saw people who had constantly rejected SGML as a message vehicle or a document format completely change their mind and adopt the new markup metalanguage as if it were the ultimate panacea that resolves all problems and even cures leprosy... There was almost no difference at all between the SGML and XML versions of the  messages or documents they had to write, but they were happy. Suddenly, the whole world was implementing SGXML. Parsers, validators, browsers, editors, filters, batch processors, server-side tools. Just a few years later, cops in Washington State were using Microsoft InfoPath in their cars. Even in our dreams, we never expected such a deployment during the SGML era.

At some point in the future, we will finally realize that XML Schemas and Relax NG solve only a part of the document model problems we identified 20 years ago and we'll do to schemas what we did to SGML. Just be patient :-/

" Avant j'étais moche, ma vie était un enfer ; je l'ai rencontré et il a tout changé ! " -- Alice Sapritch