>>http://ayende.com/Blog/archive/2010/01/05/nhibernate-vs.-entity-framework-4.0.aspx
>>
>>There isn't much of a comparison. Microsoft should just scrap EF and adopt NHibernate as their official ORM solution.
>
>Terrific. I just received an EF book from Amazon yesterday, planning to read it on the train. Maybe not the best investment of my time at this point?

If you're interested in learning NHibernate, check out the following resources:

http://www.summerofnhibernate.com (free videos, but not of the current version. However, it was enough for me to get rolling)
http://www.tekpub.com (not free videos, and I haven't watched them yet, but I've heard they are excellent)
NHibernate in Action book