If "quite pricey" is more than ~$1000 then it is too expensive. $1000 is the cost of a 17-40/f4 plus add a bit for IS. If it is getting towards $1300 or more then Canon can shove it where the Sun don't shine.
The 17-40 F/4L, 24-105 F/4L IS, 70-200 F/4L, etc. are in that 'entry level L lens' bucket where you get big upgrades over non-L glass, like better build quality, weather sealing, sharper, quicker focusing, etc. but you don't get best-in-class IQ or the fastest apertures.
For more money, the 16-35 F/2.8L II, 24-70 F/2.8L II, 70-200 F/2.8L IS II, etc. represent the high end of Canon zooms and you generally net better IQ or can pull off more shots (i.e. speed) with those lenses.
So Dilbert, before I set a price limit on it, I think it all depends on what 'bucket' they put a new wide lens in:
- If it's a spiritual successor to the 17-40 f/4L -- possibly Canon's highest selling non-kit L lens -- even with IS the price should be around $1,000-1,200 at first offering. That lens is a 7 out of 10 lens and should not be priced like top-end pro gear. Even if they (likely) add IS and (undoubtedly) improve the corners over the current 17-40, an F/4 wide zoom shouldn't command a very high price.
- If it's a spiritual successor to the 16-35 f/2.8L II, you are talking $2,000-2,500 as that would be a best-in-focal-length offering from Canon, aimed at pros and not enthusiasts. (Keep in mind, the current II version is still going for something like $1,600-1,700 before rebate.)
- If it's altogether something new and desired by pros and enthusiasts alike, say a 14-24L f/2.8 -- look out. They could ask for the earth, moon and stars and people would pay it. I'd see that lens offered at a very high starting price for the long-time wantees, perhaps $3k, and then walked down over time to where the Nikon offering is ($2k I believe). And if that 14-24L F/2.8 is either front-filterable or (more likely) compatible with Lee's oversized filter apparatus on day one, some folks would give vital organs for it. Such a lens would be priceless for some folks.
As much as it pains me, I have to say I'm probably leaning a bit more to Dilbert's side on this one.
For one thing, neither the categories nor the assessments are quite as clear as ahsanford states.
I don't know where the 24-70 f4 IS would fit into his categories. But, it is selling at $1,200 including rebate, although I don't know whether or not anyone is actually buying that lens.
I don't know why someone would call the 17-40 F4 a "7" out of 10. Virtually every test and review shows it performs every bit as well as the 16-35 f2.8. I suppose you can "score" it slightly lower because it is an f4 lens, but only if one needs f2.8.
I'm always amused at those who make price distinctions between "pros" and "enthusiasts" assuming that pros pay more than enthusiasts, when in reality, it is usually just the opposite. Enthusiasts are more likely to pay top dollar because they have the discretionary dollars to spend. Pros need to worry about mundane things like return on investment.
Finally, I suspect that someone may be spending too much time on internet forums if they really believe there is such a huge pent-up demand for a $3,000 ultra-wide 14-24 f2.8.