I'm reworking our software to pass the "Certified for Windows Vista" Test Cases. You can get this lengthy document from:
Even if you don't go for the logo, it's worth reading this document. There are a lot of changes in Vista that affect client application development and you're in for many technical support headaches if you don't plan for them.
One of the logo requirements is to use an MSI-based installer. This was a big change for us. We've historically used a minimalist custom installer because our entire application was a single statically linked executable that was 500KB. I searched everywhere for an MSI-based install generator that didn't add 1.5MB of overhead. We couldn't use the VS2005-based installer because we needed a wrapper that could handle dependency installation (such as installing the MSI installer) because we still support Windows 98.
We decided to use Advanced Installer from Caphyon. It does everything we need, is reasonably priced, and has decent technical support. Yesterday Caphyon released version 4.6 which adds several features for Vista logo requirements. I've now been using Advanced Installer for six months and I've been very happy with the choice.