Adobe's Portable Document Format (known to the faceless masses as PDF) has long been a popular format, and has pretty much been a de facto standard. Adobe's decided to take the next step and have PDF officially adapted as an open standard by submitting it to approval of the International Organization for Standardization (ISO).
Why now? Microsoft is moving in on Adobe's territory with its XML Paper Specification (XPS), which has also been submitted as an open standard, after Adobe pressured the EU into preventing Microsoft from bundling XPS support into Vista and Office 2007, arguing that it would be undercut competition.
It'll be between one and three years before official approval is granted, but when it comes around, consumers may very well have their choice of open, free formats. Which is good news all around.