Is Linq included in .net 2010
It certainly is. There are too many features\technologies that are tightly integrated with Linq (ADO.NET entity framework, Linq to SQL and what not). Linq is a major direction for Microsoft and it would be at least 'weird' of them to abandon Linq after so aggressively pushing it forward.
Yes. Visual Studio 2010 targets versions 4, 3.5 and 2.0 of the .NET Framework. LINQ is included in projects that target 3.5 & 4 and there's no reason to think it will be dropped in any upcoming version.
What may be confusing is that LINQ to SQL is not going to be actively developed in the future. Instead, Microsoft is encouraging developers to use the Entity Framework. However, LINQ to SQL will still be part of the framework - it just won't have any new features.