LINQ itself does - but strictly speaking, LINQ isn't a language
feature. The word LINQ only appears in the C# 3 spec in namespaces.

The C# 3 feature *enabling* LINQ is query expressions, and they can
work with anything that provides the appropriate methods. For instance:

public delegate TRet FakeFunc<TIn, TRet>(TIn x);

public class FakeLinq
{
   public FakeLinq Where(FakeFunc<FakeLinq,bool> x)
   {
       return null;
   }
   
   public T Select<T>(FakeFunc<FakeLinq,T> y)
   {
       return default(T);
   }
}

class Test
{
   static void Main()
   {
       var x = from z in new FakeLinq()
               where z==null
               select z.ToString();                
   }
}

Not an IEnumerable<T> in sight. The above would compile with the C# 3
compiler targeting .NET 2.0, and run under .NET 2.0.

That is true. I am thinking a bit too Microsoft today.

LINQ syntax, itself, is built into the language. There is much of LINQ that
requires support of the Framework, so I guess that feature does sit on the
cusp of language and Framework.

Back to the original question: I am not sure anyone knows if and when a SP1
is planned and I am sure it would be NDA information if they knew.

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