As I reported earlier, NI has set up a webpage for Vista information. A recent addition is a good summary overview of many of the various changes in security that Microsoft put into Vista - including the whole "virtualization" support for legacy apps. Rather than repeat the information, I recommend that you check out the article here.
I've been living these issues for the last six months as I work with others here at NI to ensure our software is ready to go when Vista becomes widely available. If you have any questions about Vista, or the article, please feel free to drop a comment here or shoot me an email.