Same problem here trying to use ObjectDatasource within a simple report.
I try to reproduce the example shown into what changed 2010 webinar but I don't have the Design Data Layout wizard form shown.
When finishing the wizard, I have the objectdatasource into the bottomed panel shown but if I try to set a textbox value to a field, I have nothing into fields list. When I try to see my datasource with Telerik / Data explorer, it says I have no datasource.
Edit : It seems to be a known bug : http://www.telerik.com/community/forums/reporting/telerik-reporting/setting-ods-parameter-value-data-explorer.aspx
Edit2 : after deleting ODS parameters, still same problem here : no datasource available nor data fields visible...
So i found out why there were no fields. I needed to set the datasource on the crosstab. I selected the crosstab by clicking on the top-left corner of the crosstab. Then setting the datasource in the properties window.
By the way, i found out that when using the crosstab, i shldn't use the report wizard.