In running down this problem this weekend I found a very comprehensive article on troubleshooting error 99 written by a service center ("Canon's Error 99: the Man, the Myth"). It included one thing I never thought of which was to swap out the date / time battery. I did and unfortunately was not the issue.

Replace or repair?

So today I have my 30D wrapped up waiting to go back to the service center; at least I am considering it. The question to me is, do I put more money into this camera considering the shutter failed only a few months after it came back from the service center? Doesn't that money put me further away from a new replacement?

The environmentalist / cheapish person in me doesn't want to throw out what was once a very good body (that originally cost me over $1300). A $300 or so repair makes it well again -- but then for how long until the next repair?

Film cameras were never designed to last the number of actuations that DSLR goes through, but is it a fair observation that they used to make them a lot better too? Certainly, DSLRs are more complex than film bodies. Pondering...