PDFCreator easily creates PDFs from any Windows program. Use it like a printer in Word, StarCalc or any other Windows application. and it is an open source project.
PDFCreator 0.98 has some improvements ,

* Uses GPL-Ghostscript 8.64 now.
* Improved PDF/A compatibility.
* New output format SVG (experimental)
* Improved check for updates on PDFCreator.
* Improved COM [...]

From OpenOffice.org 3.0 Beta Features I noticed some great features about PDF,
*PDF/A Support
In addition to the ISO standard OpenDocument Format (ODF), OpenOffice.org also supports the the popular ISO standard PDF/A. While ODF is used for editable documents, PDF/A is popular for archiving read-only versions of documents.

*Enhanced PDF Export

The PDF export feature in OpenOffice.org provides a [...]

From PC Pro, I got Google introduces Presentation PDF support,

Google has added PDF support to the presentations component of Google Docs.
Presentation can now export slides in the PDF format, enabling presentations to be saved offline. There’s also a set of PDF-based printing options that enable up to 12 slides to be printed on single sheet.

So [...]