wel some replies to some above posts as it feels needed.
i do own the mark 1 of this lens and i shot most of my photo's with this lens and always was satisfied with it untill i got my hands on a usm lens after that you cant simply go back and ignore the fact usm is by far supreme in any way and if 40 dollar is all it costs then it should be added.
i get that canon looks at sale fogures thats why they keep selling lenses that are sub par to what nikon offers in the same price range so people in the end want something better and buy a L as far as im concerned thats all canon thinks about.
as for people not wanting it wel it depends on how you look at it.
most people maby dont want to pay 40 dollar more on a kit however if you give em both in there hands 1 with and 1 without usm im fairly sure they will almost all got for the USM version and happily pay the 40 bucks extra.
people cant miss what they dont know excists but eventualy if they stick with a dslr they want something faster.
im not completely negative about this lens however i do believe canon is not doing the right thing by leaving out usm versions of there budged toppers.
i shot 3 years with micromotor lenses just fine and IQ/sharpness isnt a concern for me but focusing with thiese lenses is just awefull and thats why i am slowly upgrading all my lenses to higher end lenses not because of the IQ but because i want faster focusing.
go look at prices and check the gap in prices and lineup canon is leaving behind here just by not creating usm budged lenses.
pros will go for L lenses anyway so canon wont lose out there i dont need L build quality or looks i just need faster focus.
canon will also not get more money if i have to buy 3 L lenses to replace my current slow focus lenses as i can only spend x amount so all canon is doing is lowering the amount of units sold on the short term and forcing people offbrand.
anyway i hope canon one day willl see the light and add usm to all lenses or adds a usm series alongside the current lineup as now im fully into canon gear i cant hop to nikon as thats just to expencive so im pretty much forced to buy sigma/tamron/tokina lenses now as the L series is to expencive for the average person.
(i dont make a penny with my shots)
anyway lets just hope they get it soon the 50m 1.8 rumor upgrade would be a good start