Maybe this will help,
WaterTablesDataSet is the dataset that I use for all my data access and reporting in my application.
Dim ds As New WaterTablesDataSet
Dim ta As New WaterTablesDataSetTableAdapters.GroupLotsForUsersTableAdapter
Me.ReportViewer1.LocalReport.ReportPath = "c:\aquadatatest\aquadatavb2010\report1.rdlc"
Dim sReportDataSource As ReportDataSource
sReportDataSource = New ReportDataSource()
sReportDataSource.Name = "DataSet1"
sReportDataSource.Value = ds.GroupLotsForUsers
DataSet1 is the name I used when I was initially designing the report and I had set WaterTablesDataset as its datasource.