LINQ seems to be an overwhelming success (I've been having a hard time finding anyone with bad things to say about it), but what most people are talking about is the nice Object-Relational mapping tools. The ultimate goal of LINQ, though, includes uniting not only objects and relational data but XML. The current LINQ for XML does not support schemas, which is a significant limitation if you're trying to really unify a model; for instance, I have a client who needs to integrate two relational models, a middle-tier object model, and an XML data store. Today, we spend significant time batting back and forth XPaths and tracking them in and out of the relational model. As for reporting, the less said the better.

LINQ to XSD is the necessary next step: a set of tools for LINQ that understand the type information expressed in W3C Schemas.