Integrating SSRS + Sharepoint + Report Viewer

Scenario:

We need to display a report based on the data spread across multiple list. In such a case we won't be able to use either List View or Data View. One easier way to solve this problem is to create a custom webservice which will basically call the List Web Services provided by Sharepoint, create the dataset and return it back to the SSRS report.

One problem which we will face is while the deployment in production server. What we can do is in the report viewer control, lets take the rdl file from local instead of server. We can keep the rdl file in sharepoint list only. Thus the rdl file will be secure and can be replaced only by administrators. One drawback of the approach is that, the rdl file will not be available in the Sql Reporting Server. But compared to the ease of deployment, I think we can live with this :)