Canon’s EF 16-35 f/2.8 L II is a very popular lens, particularly for landscape and architectural photography. It has remained out of the reach of many enthusiast photographers due to its very high price ($1700, but at the time of this writing there is a $200 mail-in rebate). The lens is also not image stabilized, though at 16mm it doesn’t really need it for most applications. Canon has recently announced the arrival of a more competitively priced version of this flagship lens – the EF 16-35 f/4 IS! Some subtle differences include the new lens having image stabilization, which helps to overcome the one-stop difference in aperture in low-light situations; a 77-mm filter thread (as opposed to the 82mm thread size of the f/2.8 variant), which is a size you are much more likely to have a filter for; and the price, which is coming in at $1200. This lens is due out this June, with preorders already underway at B&H Photo and Video.
I bought one as soon as it became available. I can tell you, this is my most-used lens now. It absolutely rocked the house when photographing storms this past summer. I liked the 17-40L but this just blows the doors off any other lens I’ve used. The Fujifilm 10-24 is also an AMAZING lens if you are into the XF system camera.