whats wrong with the original 24-105L anyways?
My biggest issue with the 24-105 is vignetting at the wide end. If I have a polarizer on this lens, it really functions more like a 28-105. I find this very frustrating. The barrel distortion at the wide end is also an issue for meâ€”though it is one more easily fixed.
I tend to shoot at wider angles so, for me, anything above 50mm is a convenience. I'll use it, but far less frequently that the wider end. If there is going to be a compromise in quality, I'd like it to be at the long end of the zoom range. It's the opposite with the 24-105. (Having said that, this is the case with almost any zoom lens. It's easier to engineer longer focal lengths.)
Based on the age of the current 24-105, I would be surprised if it is replaced. It would take an additional feature, perhaps related to video, to justify a refresh. I'm actually hoping that the 5DIII includes a new 24-70 f/2.8L II as the "kit lens". That lens is past due.
+1 for the 24-70. I'd rather have less reach and better IQ.