No sooner did I read Tom’s interesting analysis of his decision to go back to wintel for his laptop needs than I am presented with a low-space dialog regarding this laptop’s internal 70gb drive. Tom notes that from his perspective, Powerbook HDs are not upgradeable. As someone who once performed a hard-drive upgrade on an original iBook, my bet is that upgrades are actually possible, but a giant pain in the neck.

Some research on the subject, for reference. Interestingly, most of this info clearly concerns older Powerbooks.