System.Reflection.Assembly.GetExecutingAssembly().GetName().Name

or

typeof(Program).Assembly.GetName().Name;

I use the Assembly to set the form's title as such:

private String BuildFormTitle()
{
    String AppName = System.Reflection.Assembly.GetEntryAssembly().GetName().Name;
    String FormTitle = String.Format("{0} {1} ({2})", 
                                     AppName, 
                                     Application.ProductName, 
                                     Application.ProductVersion);
    return FormTitle;
}