A few MacFixIt readers have recently contacted me regarding an issue with not being able to view some PDFs that were made on their OS X systems after upgrading to OS X 10.6.7. This includes viewing the PDF on their Macs, as well as seeing them on other platforms such as Windows, iOS, and Linux.
Usually PDF rendering problems can happen if the system is experiencing font corruption; most of the time this can be tackled with a general maintenance routine to clear caches, coupled with checking and managing fonts with Font Book. In these cases the problems are persisting.
In a recent Apple discussion thread, a number of people have found the issue only seems to happen when using OpenType PostScript fonts (namely Myriad Pro), and in further investigation by TidBITS it appears that the latest OS update from Apple contains a bug that breaks font rendering when using these fonts. This means that any program that uses Apple's printing technologies coupled with these fonts may have troubles printing either directly to the printer or when creating PDF documents. Programs like Adobe Creative Suite that use their own printing technologies should not be affected by this issue.
The issue appears so far to be limited to OpenType PostScript fonts, and does not affect TrueType or other font formats. You can see which fonts on your system are OpenType by selecting them in Font Book and pressing Command-I to get information on them. You should see a list of properties such as the font's name, style, language, version, in addition to a "Kind" attribute that will state whether it is TrueType, OpenType, or another kind of font.
Hopefully Apple will tackle this problem soon, but if you need to use Apple's printing technologies, then for now the only option appears to be to downgrade to OS X 10.6.6 by reverting to a backup using Time Machine, or by reinstalling OS X from the installation DVD and then downloading and applying the OS X 10.6.6 Combo updater.
If you do not need to use Apple's printing technologies, then beside avoiding OpenType PostScript fonts in your documents, one option is to use Adobe PDF to create PDF documents and then print them if desired. Install Adobe Acrobat and then "Adobe PDF" should appear as a printer option in OS X that you can use to create the PDF.