Have had my NEX-3 for a year now - it's been replaced in the market by the NEX-C3 but might still be available at a discount. I got it with 16mm and added the 18-55mm later (and later still the 18-200!), originally to provide good low-light indoor images while traveling without my dSLR (which is just too big to take on business trips). But I found it was able to replace my dSLR for almost all photo opportunities - even fast action like sports photos - usually a dSLR domain - can be achieved with this. And the reduction is size and weight is most welcome!
Pros: image quality + image options (eg P, A, M, S modes and others) + firmware updated by Sony to v4 means more new features, free, like new image modes, focus peaking for old manual lens focusing + HDR (joining images of different exposure for shadow detail) works well + panorama mode + ability with inexpensive adapters to mount almost any lens ever made for old SLRs! hence great for experimenting!
Cons: 18-55 is rightsized for the sensor size, but would be nicer if 3cm shorter for easier travel - 18-55 zoom ring is a little uneven after some use - OK for casual use but not pro quality I guess - battery cover is a bit flimsy - batter charger a little on the large side - can be difficult to avoid camera shake with other lenses, although not much of an issue with the 18-55 as that has stabilisation - small body size can make tripod use problematic
This is a very well made, versatile camera and I am extremely pleased with it. Having used both digital SLRs and compact cameras in the past, to me, this is the perfect marriage of the two. The 'intelligent auto' mode allows the camera to be used as an everyday point and shoot with no fuss and excellent results. When looking for something more professional, all the facilities of an SLR are available and produce high quality pictures on a par with entry level to mid range DSLRs. The menu system seems very well thought out, but can feel too simplistic at times, plus the amount of menu navigation required to change basic settings may come as a bit of a shock to regular users of more professional cameras. The quality of the screen is also brilliant, the only other screen I have used with resolution this high is the iPhone 4 with its 'retina' display.
The only major problem I have is with the 18-55mm lens, which suffers from quite serious barrel distortion. Any straight lines towards the edge of picture appear noticeably warped, totally ruining some pictures I have taken. The zoom ring also feels quite rough when turned, probably the result of part of the barrel being made of plastic. It's my guess that this lens was made cheaply to keep the costs down for beginners, who seem to be the main focus of Sony's marketing of this camera. My advise would be to buy the just the camera body and purchase an E-mount adapter so a different lens can be used. I can't speak for the 16mm wide angle lens, which is supplied with the camera in a different kit, but it would seem more sensible to avoid the E-mount lenses for now, or else you will be stuck with hundreds of pounds of useless lenses if you ever decide to buy a different camera.
All in all, this is a great camera, both for beginners and professional and its a shame it had to be let down by Sony's lenses.