If the new 24-15 is meant as a kit lens for FF, and replacement for the 28-135, then it will be priced at $599.
When Canon drops the 24-105L, its replacement (24-105 MkII L) will have all the bells and whistles; more stops, more IQ, and more cowbell. Price? $1999, quickly rebated to $1799.
If, on the other hand, the new 24-105 is going to be it for a few years, then it will be rolled out at $899.
Seems like STM for video would be the only reason to get this lens. Canon already has a non-L general purpose zoom that is lighter and much cheaper than the 24-105L. The 28-135 is virtually equal to the 24-105 in IQ at f8 and higher where I generally use it. And it's dirt cheap used, having been offered as part of an ill-matched kit with the 7D. What Canon really needs (i.e. what I would like) is a walkaround zoom that can go from ultrawide to short tele. Say, an EF 17-70 variable aperture with IS.
Seems to me that this is one of the most exciting Canon lens releases for a long time. Subject to IQ its this lenses' price point that is so attractive, even in the UK where we are used to being gouged on new camera kit this zoom is available for preorder at less than £500. In a year or so it will be nearer £400 which is potentially very exciting.
But the real point is that the release of an affordable wide range standard zoom suggests the release of an affordable full frame "Rebel" to use it on, and I define affordable as 50-60% of the cost of a 5D3. Full frame may well now be poised to eat into the budget cropper market, and that would bode well for the many amateurs who cannot offset kit purchases against tax, and so baulk at the cost of existing FF bodies. Value for money may well be the touchstone of the market over the next couple of years even at the full frame level, just as well for those of us who can't/won't pay £10,000 for a telephoto.
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