I've used development environments as diverse as the LISP environment on dedicated Symbolics machines, Smalltalk, Centerline C++ on Sun,Borland's C++ IDE in the early 90s, and Borland's Delphi. After working extensively in Delphi for years for both Windows and Web applications, I switched to Visual Studio for Web Development in 2003. I can say without a doubt that Visual Studio 2005 is the most productive environment in existence.
Everything about this environment save one thing (more below) is extremely well done. Some highlights in no particular order:
* The Intellisense tools are smooth and very quick (especially compared with Delphi)
* The project model is clean, simple and easy to modify (just copy files).
* Preparing a web site for distribution or upload is ridiculously easy
* C# is easily the most productive language available for general business development (I once mentored C++ for new developers at Bell Labs and have written my own Smalltalk environment so I don't say this lightly)
* Microsoft has made enormous strides in making web development as easy as VB's original drag and drop model
* The environment is easy to customize with macros, etc. and features a stellar array of productivity-enhancing features (outlining, refactoring, snippets, etc.)
* There is a broad selection of third-party tools that integration with Visual Studio.
Now, for all of its advantages, the one area where they could stand significant improvement is in the help system. For example, the help screens for most environment objects is essentially nothing more than the inheritance tree. It does essentially nothing to educate you about *how* a feature is used. This has been a problem for Microsoft for years and, unfortunately, VS 2005 has done nothing to improve the situation. Thus, you will want to have lots of web and/or written resources on hand when developing.
I cannot comment on the team development features as I work alone on the software sold by my company.
In balance, I've simply never seen a better development environment.