Microsoft has published a list of programs that will not work or that will suffer from reduced functionality after the installation of Vista Service Pack 1.
The list of programs consists mostly of security applications, such as Trend Micro Internet Security 2008. However, programs such as The New York Times Reader application also feature on the list. Users are advised to install updates from the application vendor to fix the problem.
None of these are really big sellers, so the impact should be small. However, as more users install SP1, will we see a rash of programs that are incompatible? You might want to keep checking that service bulletin.