According to Bob, HTTP endpoints are deprecated in SQL Server 2008. With HTTP endpoints you had the possibility to expose stored procedures and stored functions as SOAP web services to the outside world of SQL Server 2005. But with SQL Server 2008 you have to choose some other ways, if you want to accomplish the same thing.
You could use ADO.NET Data Services - formerly known as Project Astoria. With ADO.NET Data Services you can implement RESTful services over any type of data. You can also supply directly a stored procedure as input. So it seems that ADO.NET Data Services is the replacement for HTTP endpoints in SQL Server 2008 and any further version. This means also that the .NET runtime is getting more and more power on the Microsoft platform, because everything has to be done with .NET - also exposing stored procedures from SQL Server...
-Klaus