Looks like my Canon EOS 1D Mark III is one of the affected bodies that will need the sub mirror fix. As I have mainly used manual focus with the 1D Mark III (Zeiss ZF lenses), I have not been too bothered, but I have found that the 1DM3 focuses inaccurately with a variety of lenses under conditions that should have resulted in perfect focus (fixed subjects, not ones in motion).
I haven’t done a scientific A/B test to verify that the 1DM3 focus is in fact worse than other cameras, though it seems so. Read my Focus Accuracy article for insights into focusing as a general issue. Not described there (yet) is the fact that recent tests with a dozen Canon EF lenses using the Canon EOS 1Ds Mark II showed not-quite-right focus with fully half the lenses (not wildly off, but enough that a slight manual tweak showed better contrast and slightly better resolution). Still, the 1DM3 does seem worse than any other brand/body I’ve used, but not under all circumstances.
One can complain about Nikon taking a long time to release newer technologies such as full-frame (see Goodbye Nikon?), but in the past few years it seems that Canon bodies have needed more firmware updates, and now an actual hardware modification in a professional caliber body. Was it rushed to market to beat Nikon?
What working pro wants to send in the 1DM3 for service for an unspecified number of days/weeks with no loaner body? (Rent one at $150/day for two weeks?) And given that the serial number range covers 45,000 cameras, the time required and the quality of the repair is certainly a concern. Yes, one expects warranty coverage, but that’s the bare minimum to expect, especially after a four month denial by Canon of any problem. No one buys an EOS 1D Mark III as a casual camera—customers deserve a substantial and tangible acknowledgement of the inconvenience and expense. Doubling the warranty to two years instead of one year would seem appropriate.