I work at a web development company, so our aim is ASP.NET and IIS. Currently we use a mix of Visual Studio Web Developer 2008 SP1 and Visual Studio Standard Edition 2005, and we're about to purchase the same edition for all development teams. We work in teams from 3 to 8 developers per team.
Looking at the feature matrix of Visual Studio products I can see quite some features that I don't even know what they do, or have 3rd party alternatives (like NUnit vs MSTest). If you've got a second, could you please post what edition of Visual Studio you or your company uses, and what the main reason(s) are?
Update:
We're not really trying to choose between 2005 or 2008, but it's the standard/pro/team suite differences and benefits of each edition that we're trying to get a grip on.