For simple apps, yes. But actually I was surprised to find out that they have been on and off plans in attempt to kill linq2sql and actually if you inspect the produced sql code(out of the box) .. well it can use a lot of optimizations.

I do think o/r mappers are the way to go, although having better tools does not mean that you should start handwaving when it comes to db internals.

Maybe if all you're doing is writing silly blogging software, then you can get away with that. I need to develop apps the report live on nation-wide sales and inventory data, down to the individual shipment. You start dealing with a database intended to hold 10, 20 years of warehoused data, application languages turn into a blur in the background.

It is, to use a Spolskyism, a leaky abstraction.