dynamic range: X-E1 vs Nikon

I've been using Canon digital SLRs (1D, 5D, 7D) since 2004, and grew more and more tired of certain aspects of the system.  For the purpose of this post, DR and the ability to lift shadows is one of the most important motivators to leave Canon.  Canon's product philosophy started to get to me as well, but this is beyond this question.

I was considering Nikon D600 - looks like an amazing all around camera with a great sensor.
At the same time, I kept an eye on large sensor mirrorless as they were getting better and better by year.  I wanted smaller size and high IQ at the same time, but m4/3 and Sony NEX never impressed me enough to buy into their systems - they are great, but I just don't like different aspects of them.
However, Fuji F caught my eye after they announced X-E1.  The lens system promises to be great as well.  The form factor and interface are important pluses.  I still shoot film for everything other than family and events and use Nikon F3 and Fuji GS645.
So, everything including the IQ is great overall.  But how about the DR?  How does it compare to the latest Nikons?
Also, how sensitive are these cameras if used in rain?
Thank you,Igor.