After five working days (plus a sixth since I'm not one to immediately complain) had passed without the promised technician so much as making an appointment to fix what had gone wrong the last time a Dell technician repaired my laptop, I called the Dell hotline again yesterday. After plenty of time on hold, I was told that they were having trouble getting spare parts atm and were hoping to have a technician call me before the end of next week once they had their parts again. They didn't say why they were having trouble getting parts delivered, but I assume it's because of the earthquake and all subsequent events in Japan. They wouldn't be the only ones.
Not exactly the news I was hoping for, but well, I guess that's a case of force majeure and not Dell's fault.