Here are a couple of leaked images of the previously rumored Canon EF 16-35mm f/4L IS and EF-S 10-18mm f/4.5-5.6 IS STM lenses. Expect an official announcement later tonight or tomorrow.
The 16-35mm f/4L appears to be slightly larger than the popular Canon 17-40mm f/4L lens. The 10-18mm may end up being less expensive than we initially though because of the move to a plastic mount (as compared to the metal mount of the EF-S 10-22mm lens). It looks like a very lightweight and compact lens.
[via DCI]
Great news! I hope the quality is good so many people will spend time to look up on Amazon, Kijiji & eBay for people who are dumping their 17-40 L f/4 (or 16-35 L f/2,8 for the IS) for cheap to get their new extra 1mm & IS toy!
Checkout the comparison 17-40 L vs. 16-35 L II and see which is SHARPER:
http://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=412&Camera=453&Sample=0&FLI=0&API=0&LensComp=100&CameraComp=453&SampleComp=0&FLIComp=0&APIComp=0