Why use VB.Net?

Visual Basic. Net (VB.Net) is an evolution of Microsoft's VIsual Basic that is implemented in the Microsoft Dot Net Framework.

The main reason that led to the evolution of VB.Net is due to the lack of backward compatibilty with the older versions in Visual Basic. VB.Net has overcome this feature in the .Net framework.
VB.Net has a compact framework and better VB upgrade wizard. A lot of improvements have been done to take care of performance and reliability of the .NET IDE and runtime. These were some of the major drawbacks of VB 7.1

VB.Net is not entirely a new language. It has been developed from Visual Basic with some additional functionalities. Some new features like structured exception handling and short circuited expressions have been added in the .Net. There are some other slight variations that have been made in .Net in order to adapt itself to the .Net Framework , for example the short and the long integers have been doubled in .Net

Also the programmers faced lot of performance and maintainability issues with the previous versions of Visual Basic. This was one of the reasons to find the improvised version called VB.Net.

VB.Net has extensive documentation that covers the changes in the syntax, debugging applications, deployment and terminology when VB project has to be migrated to the .Net framework. So the programmers need not worry about rewriting the code from the scratch in .Net framework.
Also, VB.Net is backward compatible. Any new versions of the project developed in VB.Net can easily be traced back in the .Net framework with no or little efforts.

Hence, the developers now a days are preferring Microsoft's VB.Net than the traditional Visual Basic.