Expanding openness

Widening the concept of open Open source is open to a limited number of typically already high-powered developers. Open data is open even to people who just want to move information from one program to another.
Welcoming new communities XML may bring open source developers into closer contact with closed source developers, users, and communities of open source developers they wouldn't have worked with otherwise. Not-invented-here doesn't work very well in XML
Accepting (lowered) integration costs Different communities will have different needs and different XML formats. There are real conversion costs, but those conversions are at least done in the open, where results can be tested by inspection.
Looking forward While open data hasn't yet reached the awareness level of open source, it offers an opportunity to change the styles in which we work quite drastically, giving users and programmers more access to the power they need to solve complex problems.