Locally I don't see them anymore. If I do, they are just counted as tabletop terrain- part of the table.
With my Grey Knights a defense line used to be an auto-include, not any more.
I think partially b/c the novelty has worn off, partly b/c the advantage you might have gotten by the state of the game when GW introduced them was something new, but has now settled down or points better spent. Partially also b/c many tournaments have rules on what you can bring with fortifications.
Never saw a fortress of redemption on the table...