.NET still the best choice for business
Our business is a web-based service and we're very happy that we picked .NET to build it with. The .NET class library is excellent, far richer than other platforms we evaluated -- the only missing or weak area being charting controls. However, Microsoft's purchase of Dundas a year or so ago, and MS Chart now being a free add-on, has more than remedied this.
We've now built up a strong library of our own extended and custom controls, which means development of new functionality is rapid, consistent, and rock solid. Compared to previous projects done with PHP (for example), we are in a much better place.
Java was a serious consideration for us, but given that cross-platform was of no interest, and the relative strength of Visual Studio as a development tool, .NET has proven to be excellent.