. . . and I've never seen anyone using a Leica for birding. Not the first choice of camera for that kind of subject matter. The typical Leica street shooter is usually unconcerned about moire.
Anyone who photographs birds and wants to capture the beautifully intricate details of the incredible variety of feathers should really lean toward the D800 IMO. It makes no sense at all to invite endless hours of moire filtering work in NX2 or Photoshop - work which may end up softening everything slightly. You're likely to end up with superb D800 bird photos when using a D800E. Feathers invite moire optical effects, so why bother with a camera which will aggravate the situation? IMO that is.