After deciding that I wanted to query the much reveled OData services offered by Sharepoint 2010 I ran into multiple issues (now which I’ve resolved).
This is the service endpoint
http://<hostname>/_vti_bin/ListData.svc
1) OData services do not work over HTTPS. I’m assuming this is related to configuration of WCF. This is a key point to remember.
2) Installing of the ADO.NET Data Services v1.5 CTP2 on the Sharepoint 2010 Server. Do an IISRESET or reboot after this.
3) Ensure that there are no corrupt lists on a site. If there are you’ll be able to hit a specific list but not hit the endpoint. You’ll keep getting prompted with the NTLM/Keberos login from your web browser and never get logged in. To remove a corrupted list (mine happened from upgrading from Sharepoint 2007 to Sharepoint 2010 without installing custom list types), run the following command from the Sharepoint Powershell Prompt (thanks to Harold van de Kamp’s blog entry on this one.)
stsadm.exe -o forcedeletelist -url <url>