Sony announced yesterday that they'll share the E-mount specification (mount used by the NEX series) free with any interested third-party lens makers. Finally. Someone gets that the lock isn't selling your own lenses, it's instead getting users invested in lenses with a certain mount. Sigma has already announced that they'll support the mount and is showing a 30mm f/2.8 lens.
Lately the m4/3 group has been getting all the press regarding lenses, as joining that consortium nets you the mount specs, and we now have six companies officially signed up to create lenses for that mount (Olympus, Panasonic, Cosina, Sigma, Zeiss, and Schneider).
Lens choice is one of the things that have locked people into the Nikon/Canon duopoly over the years. While other players produce a number of lenses, the sheer choice in the Nikon and Canon mounts has led people towards Nikon and Canon cameras. For the first-time purchaser who just goes all-in-one, that isn't a big thing, but the camera companies make good money hooking people into systems. And those systems have been proprietary for far too long.
It's time that Nikon and Canon dropped the proprietary tag on their mounts and divulge the full specification. Given that in the Nikon mount a lens registers itself to the camera with a "code," it's time those codes got opened up, too.
Meanwhile, Sony has updated their NEX lens roadmap. 2011 will bring a Zeiss 24mm, plus 30mm, 50mm, and 55-200mm lenses. Three further lenses will be released in 2012.