I just stumbled across the VS2010 "upgrade or die" confrontation for the RDL report designer. Before I destroy a perfectly good monitor, I decided to take a deep breath and calmly ask if anyone can give me the real scoop on what is going on with RDL client-side reporting. I've seen it said that it can't be done with RDL 2008. Is this true, and if so, is it a deliberate attempt on the part of Microsoft to put its so-called partners in the ground, or is there a less sinister explanation?
The new ReportViewer has some fine advantages over the old one (Tablix, RichText), the designer is not bad, but there is a big bug in and MS seems not to be capable to fix it: It's no more possible to navigate to child objects within expression.
If you use business objects you will probably better wait upgrading. Else you will find yourself writing a lot of wrapper code or extendind your business-objects with unnecessary code. The problem description can be found here:
This post shows you the problem:
http://stackoverflow.com/questions/2551969/child-objects-in-rdlc-studio-2010rc
There are also some other issues but most of them are solvable:
http://msmvps.com/blogs/bill/archive/2010/04/19/upgrading-report-applications-to-4-0.aspx
As you wrote in your question, ReportViewer 2010 has a new format (V3, 2008). Therefore you need the ReportViewer Redistributable (2010) for your clients.