We're jumping from iText 2.x.y to 5.0.0 for the following reasons:
We want to use the same version number for iText and iTextSharp.
From now on, the iText.jar is compiled using Java 5 (instead of with the JDK 1.4).
The F/OSS license has been upgraded from MPL/LGPL to AGPL.
The package names have changed from
The toolbox and RTF support have been removed: they are now in a separate project at SourceForge.
Note that because of the change of the package names, you can't upgrade to iText 5 without changing your code.