Just picked up this article on java.dzone.com Martin Fowler on ORM Hate. Fowler always has very interesting things to say due to his expertise in the industry.
There has been a lot of push-back against ORMs, especially in the NoSQL space and Fowler takes some time to talk about this. ORMs are a tool like any other and a lot depends on how we use them. One of the biggest complaints is that they are a big black box, which can be true, but they also are a HUGE help with relational mapping. Even manual SQL queries force you to do some sort of mapping operation since you are going from relational to object.
One trend I see is incorporating NoSQL support into various ORMs. Document stores seem to be popular for this, possibly because of the simplicity of the data model. The capabilities of each store however, very greatly, so this is difficult. Some stores like MongoDB and CouchDB provide support for more advanced queries, even SQL-like queries while other stores like Riak provide relatively limited support, essentially key-only access. Basho is working on adding more advanced support now with secondary keys and Riak Search.