I asked this question reguarding the use of Linq-2-Sql with the Rob Conery's use of the Repository in his MVC Storefront app and got an excellent response from Matt Briggs:
L2S is used to generate the DAL, but the only thing that should know about the DAL is the repository, so a translation is made to his domain objects.
I think L2S (and Robs open source DAL, SubSonic) are great projects, but more designed for smaller, 2-tier apps where something like the repository pattern is over kill. The storefront is also a good illustration of why the additional complexity of NHibernate can be important, he could have saved himself a lot of code by going with something built to handle that sort of scenario, rather then doing it all manually.
So my question is what OR/M tools are out there that are more robust, more stable, and support the Linq IQueryable functionality?
Thanks!