Well this should be interesting. If this works, it will be a number of firsts – first email sent via Palm over wifi, first typed with my new Thumboard app (link to follow since I’m not sure how to make pretty links here), and finally first official post-by-email.
Whew, the suspense is about killing me. Let’s see what happens.
EDIT: Well, in the interests of full disclosure, what really happened is this – nothing got posted for a while, and then I checked and it turned out the cron job wasn’t set up right. And then when that kicked in, the email got posted, but the PHP that parses the text of the email was processing newlines wrong, so I had to clean it up a bit. But—once I did that—it worked! 
So I’ll leave it here for posterity’s sake. Oh also I’ll link to Thumboard if anyone’s interested. It’s pretty easily hackable also, for anyone so inclined.