EPS graphics print poorly from PowerPoint 2007
When you print slides that include inserted EPS graphics to a PostScript printer or to a printer driver that makes PDFs (Adobe Acrobat, Jaws PDF Creator, several of the free PDF programs based on GhostScript), the quality of the graphic is poor. Text may look distorted and can get converted into graphics rather than editable text; gradients become blocky, etc.
In addition, links in the PowerPoint file aren't converted to equivalent links in the PDF when you use some PDF-assist add-ins.
The same problem does not occur in PowerPoint 2003 and earlier.
In the mid-1980s, Adobe published a fairly comprehensive and simple set of specifications for how programs should import and print EPS graphics; these are freely available.
PowerPoint 2007 doesn't follow the specs. Instead of passing the PostScript portion of the EPS graphics directly to PostScript printers as it should, it converts the Postscript to a preview image (in the rather limited EMF or WMF formats) and throws the actual PostScript (the good stuff) away. It uses its own preview image for display and printing purposes.
As a result, any intelligence built into the PostScript (and there's often a lot) gets tossed out and a relatively crude image is substituted.
The hotfix mentioned above changes this behavior and forces PowerPoint to retain the PostScript and pass it to the printer when it's appropriate.