New in SQL Server 2008 is the RDLOM, in which you can use Microsoft.ReportingServices.RdlObjectModel.dll to create your RDL’s programmatically within Visual Studio. Apears to be a very powerfull tool!
A few things to keep in mind:
- Not officially supported
- Use at your own risk
- Doesn’t validate RDL semantics
Theo Lachev has a free sample from his book which you can use to get started: