1 – Nex5n and Nex7 can use phase detection with Alpha mount lenses, which makes focus much faster.
2 – Nex5n was just reviewed by Dpreview.com (which is known among photogs as a reliable and competent testing shop) and gave it's Gold Award.
3 – the review you have read was done with the older models. New models Nex5n and 7 are more advanced and have more features and options. When the magazine issue went to print, the new Nex models have been just announced. Only a handful of camera review shops had them for testing and all of those had signed NDAs. So even though 5n and 7 were "included" in the review – they were compared only based on the published specs and not an actual test. Furthermore, of all the camera's in the article – it was the lightest camera with the largest sensor (here, larger is actually better), highest video framerate/quality AND widest ISO range.
4 – why does it kill it for you? If it works well – why do you care if it is one or the other?
5 – can any other smaller/lighter camera be used with as wide lens collection as Nex and have full AF and not require manual mode?
6 – Nex5n was recently tested against a $7,000 Leica M9 – which is one of the best small digital cameras. Only it can't use nearly the same number of AF lenses as Nex. Even with a basic kit lens Nex did pretty well. Leica may not have had the most expensive lens mounted, but a 50mm prime with a price tag of $350 vs a kit lens thrown in with the camera should give you an idea. Now if one was to put a Zeiss lens on the Nex – Leica would have really hard time justifying the price tag of the M9.
7 – As i said before – you can use nex with 16mm slim, wide angle or mount it on a 600mm f4 prime, 300mm f2.8, 50mm f1.4 or any other Minolta/Sony lens including Zeiss and get phase detection AF to boot.
Here are a few excerpts from the review:
The NEX-5N's image quality is excellent. The 16.1MP sensor in the 5N is capable of capturing images that rival some of the best APS-C format DSLRs on the market, and up to ISO 6400 image quality is impressive. Even at ISO 12,800, image quality is perfectly acceptable for online use and for small prints, and far ahead of most of the NEX's Micro Four Thirds competitors
In terms of image quality the NEX-5N sits untouched at the top of the mirrorless interchangeable lens compact category. The low-light capability of its APS-C format CMOS sensor matches or exceeds what we've come to expect from the best of the current crop of APS-C DSLRs as well. Considering its sub $700 price point this is truly impressive, and makes the 5N a very attractive option for anyone looking to upgrade from a compact camera, or even as a second body alongside a more conventional DSLR outfit.