I almost forgot to post about this; next week holds a seminar on NHibernate, Castle and MS coming offerings of EF. I will be talking about NHibernate and castle activerecord and my colleague Truls will talk about MS Entity Framework. It's an overview, which we hope will give developers looking to use OR mappers a bit of background, to aid their decision making. We call it "Data access showdown"! Do stop by!