Querying list data in SharePoint 2010

One of the big changes on the development side in SharePoint (Foundation) 2010 is how list data can be retrieved.

Client side (or external server)
Two new methods:
- ADO.NET Data Services, using REST web services (http://msdn.microsoft.com/en-us/library/ee535480.aspx)
- Client side object model (for data retrieval samples, see: http://msdn.microsoft.com/en-us/library/ee539350.aspx)

Still supported for backward compatibility:
- Web Services, e.g. the Lists web service
- RPC calls using the owssvr.dll assembly

Server side
New method:
- LINQ to SharePoint Provider (examples: http://msdn.microsoft.com/en-us/library/ee538250.aspx)

Already available method:
- Server object model (SPQuery and CAML)