Been using an NEX-3 with Sony 18-55 lens for several months and like the combination. It takes good photos and it's compact size easily fits inside the pocket of my lightweight walking jacket. For me this new zoom lens, although not so far from Sony's price, is a welcome Emount addition. To be able to get up close and relatively inconspicuously to subjects and still not lose out on landscape shooting when I need it is my ideal solution in a lens. Sure, it adds to the size of the NEX cameras but I see nothing wrong with carrying the zoom in one pocket and the camera in another. Still much more convenient than hauling a much heavier traditional dSLR either around my neck or in a large pouch.
I intend to purchase one of these lenses and will probably opt for Tamron particularly if that price comes down further but I have a question here before dropping Sony., I've been told that the Tamron IS system is better than the Sony one. Can anyone comment on this