I sent in a note (short, polite, to the point, no shouting, no screaming) to s_jobs@apple.com. I got a phone message from Apple Executive. I took the eMac to the local Apple Store Tuesday afternoon. They said they'd have a look and call me. So far they haven't called, but then I really didn't expect a call for at least a week to ten days. If they haven't called by next Friday, on Saturday I'll call them. Odds are that they'll tell me it'll take another week or so, 'cause odds are that they don't have motherboards hanging around the shop and would either have to ship the eMac to where the motherboards are or to ship in a motherboard, and that'll take a few days either way. I've budgeted 15-20 days as a reasonable turnaround time.
If the motherboard dies in another 18 months, well that's 3 years use out of it. I won't complain.