In addition to the expensive dial replacement by Canon, or as an alternative to it, another solution to the mode dial problem could theoretically come in an optional firmware upgrade allowing users, via custom function setting, to choose to consign 'B' and the auto 'green' and 'CA' settings to other modes redundantly, so that, for example, 'green' and 'CA' on the dial could both mean 'P' in actual function, and the dial's 'B' could actually mean 'M' once again. In this way, even if the dial were moved accidentally, at least the results could be far less catastrophic than if the shutter inadvertently didn't close, or the built-in flash (7D) suddenly fired in the wrong environment.
Alternatively, 'B' could be accessible as the slowest shutter speed available in 'M' and 'Tv' modes just like it was in the good old days.
With all due respect to astrophotographers, having 'B' on the mode dial is like always standing next to an abyss. All I am asking for is the option to, at least temporarily, move the entrance to the abyss a little farther away through custom settings.
While on the subject, and in case Canon is reading, although the rear quick control dial has inherited the EOS-1 tradition of being prudently provided with a lock, especially welcomed by photographers who carry their cameras around their necks, Canon has failed to provide a handy solution to the problem of accidentally rotating the main dial next to the shutter release atop the camera's grip or optional vertical grip. This is especially a problem when long lenses are mounted and cameras are slung from the shoulder with the lenses pointed in towards the photographer's body in order to protect the lens, or to enable the photographer to move through crowds or tight spaces safely or unobtrusively.
In the case of the vertical grip, the provision of an on/off switch is only a small step in the right direction, being that the switch controls the vertical shutter release as well; the control dial set to 'off' means the shutter release is also off, which is usually too extreme a precaution as it means taking the risk of missing the all-elusive "Decisive Moment."
I can't help but wonder how many engineers at Canon remember the positive feel of the old mechanical film camera controls. I have never had a Canon F1 or FT, Nikon F2 or FM2, or Olympus OM-1 accidentally be set to 'B' or otherwise change shutter speeds or apertures simply by normal rubbing against my clothing or the inside of a bag. (Some of these cameras were prosumer models, so please don't say, "Buy a 1DIV.") If you happen to be the one Canon engineer who remembers, please kindly make your voice heard.