The EF 16-35mm f/4L IS USM is Canon's first full-frame wide-angle zoom lens with a built in Image Stabilizer. Interestingly, it is an f4 lens, not an f2.8, and it is a 16-35mm, not a 17-40mm, so it sits across two existing Canon lenses. I am imagining that the f4 lens is less expensive to build than f2.8, and also easier to produce higher image quality from edge to edge. And given you can just up your ISO setting, the difference of one stop in the maximum aperture shouldn't be an issue for most photographers.
The lens features a dust-proof, drip-proof construction and uses an UltraSonic Motor for fast and silent Auto Focus. Canon states the lens will be ideal for shooting wide angle or landscape scenes.
If you use and APS-C size sensor with one of the entry level DSLR cameras, take a look at the EF-S 10-18mm f/4.5-5.6 IS STM. It also has Image Stabilization and built in STM for smooth focus, ideal for video capture as well.
For more information, visit the Canon website at www.canon.com.au.