Dustin Abbott, a friend of the site, has completed his review of the brand new Canon EF 24-105 f/3.5-5.6 IS STM.
People ask a lot if the EF 24-105 f/4L IS is going to stick around in the lineup, especially now that this lens is available. I don't have an answer for that, but there's 3 options in this focal range now if you also include the very good EF 24-70 f/4L IS. This lens is now kitted with the EOS 6D and I suspect it's going to be a kit option with all future non EOS-1 full frame cameras.
From the review
“I’m rarely a fan of variable aperture lenses, but the reality is that almost all consumer grade zooms are variable aperture. It is this concession that allows them to be lighter and cheaper. That aside, this lens provides solid optics, great image stabilization, and fast, quiet focus. It is a lens that I believe will make more and more sense as Canon introduces it as a kit bundled with cameras at a lower price point and as Canon’s next generation of full frame camera bodies add the technology that can fully utilize this lens.” Read the full review