I do understand that 17-85mm has very polarized views regarding its merits and detractions.
The distortion at the wide end is ne plus ultra (and I don't mean it in a sense of compliment) but I might be blessed to receive a relatively good copy of this particular lens - I am quite pleased with its close-up capabilities and center-frame sharpness and actually very fond of this lens. Then again, I have nothing to compare this against except for a good copy of Nikkor 50mm f/1.4 AI and non-AI versions and 28mm f2.8 AI-S (nothing from the current lineup of Canon EF/EF-S lenses).
For an APS-C or 1.6X format cameras such as 40D, 10-22mm is an essential 2nd or 3rd lens. Perhaps I'd hint my family for potential Christmas present (imagine sweeping snowscapes with bullrushes poking out of the snowdrift and a crisp blue winter sky background...). But for me, perhaps not now, as I do not have an experience with super-wideangle lenses.
After carrying 40D with me for pretty much every minute of my waking moment since its purchase a month ago, including @ work inside LowePro Slingshot 200, I'm beginning to feel that while speed of the current lens leaves much to be desired, my immediate need or satisfaction might come from a wider range of focal length (in the telephoto end) in my lens arsenal. To that end, I may go for that semi-holy grail of lenses, the 70-200mm f/4 IS. It has the same filter size as the 17-85mm and that is a big plus.
However, before delving into lens pornography, I must get to fully know the 17-85mm that came with the camera and be able to extract the best from what it has to offer, meanwhile, the extended rebate offer (that expires August 8 ) dangles in front of me like a carrot, no, like a lens of my dreams...
I must upgrade my computer too... arrrrghhhhh.
I am in a happy conundrum.