They are making the 7n which is a little bigger and has the 24mp chip. I'm not interested in the higher resolution, but the form factor on the 7n looks to be potentially nicer. I just ordered the EVF for the 5n. It is the same as the one in the a77 and a65 (and will be built into the 7n). It automatically senses whether you're using the EVF or the LCD screen and switches automatically between them.
If Sony keeps making new E mount lenses, the NEX cameras will really take off. I have compared files from the 5n to the Canon, various u4/3 I've had, my point and shoot and my old Pentax. I prefer the 5n every time. The only downside is that the shake reduction isn't in the body but rather the lens has to have it. The kit zooms have it and the new 50/1.8 will, but the 16mm pancake, 30mm macro and 24mm Zeiss don't. The adapters are a big deal as I know guys that are using their legacy glass on the 5n and they are thrilled. The focus peaking (which pro-grade video cameras have had for years) makes manual lenses totally viable. So if you've got Leica M-glass around (or any good rangefinder glass) you can use the 5n. Lots of options.
Oh, and the 1080p video is gorgeous from any of them. This was the a77 using on-board sound. It was shot 1080p then I downrezzed and uploaded to youtube. The AF tracks while shooting.
this one was output HD:
http://www.youtube.com/watch?v=GIDzeDcvh9k