Back in January, I wrote an entry about not being a fan of ORM frameworks in software development. At the time, we were struggling to increase the performance of the native mail, calendar and contact clients on the PlayBook. Our use of SQLAlchemy hindered us by trying to abstract out database calls, sometimes in ways that made the performance worse. Truly getting the performance numbers we wanted often involved solving the data access problem and then spending just as much time to figure out how to solve the problem again with SQLAlchemy. It would have been easier to just write the SQL by hand and only used on level of abstraction.
This topic of ORM frameworks sprung to my mind last night while I was listening to Dmitriry Setrakyan talk about GridGain at the Seattle Scalability Meetup. On one of the slides, Dmitriry mentions that GridGain has built a native SQL engine into the product, allowing developers to use a subset of the SQL specification to manipulate the data from their data grid. Just think about that feature for a minute - GridGain abstracted their data access method to support SQL. They're not the only vendor using SQL as an abstraction of a non-relational data store either. Cassandra also added an SQL subset syntax to make querying the data store easier as well.
I'm not trying to defend the strict definition of SQL or even advocate that these products implement every feature that you have available to you in MySQL. That's just adapting and morphing the SQL language over time and not necessarily a bad thing. Yet, every single one of them has tried to innovate some kind of new method for querying and over time settled back on things that are very close to SQL. I don't think this is caused by developer's unwillingness to change. It's because the world has vetted and refined what SQL is and come up with a very good abstraction to the problem of data manipulation.
Since SQL is a very well tested way to describe how we want to query and work with data, I can't see what value adding an ORM tool can provide. Any gains you seem to make in the very beginning of your project will quickly be lost when you start trying to boost performance or add a real world use case. Chances are you'll be able to quickly come up with some form of SQL that gets you unblocked.