I've been playing with some NEX-7 RAW files from a torrent file made available at SAR.
Here's an ISO 3200 photo which I processed from RAW using the latest beta of Raw Photo Processor (Mac only). I'm showing the resized version along with a 100% crop inset:
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Keep in mind that this is the kit lens, a beta version of RPP that doesn't fully support the camera, that the guy who took these samples was rushed and many show handshake blur, missed focus, etc.
I think the NEX-7 will probably not quite match the 5N at the highest ISO values, but it will definitely out-res the 5N and have very decent performance (at least for RAW shooters) at high ISO.
Here's the RAW file I used:
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