Quirks to fix: the bookmarklet doesn’t seem to be setting categories. It’d be nice if titleless bookmarklet entries took on the first five words of the post as the title, as per Blogger API entries. Blogger API entries need to permit TrackBack by default.
Edit: Blogger API entries now permit TrackBack by default.
Edit: the bookmarklet is working like I want it to; I think I was just confused before. Addendum: I may skip the whole Blogger API thing and write a little AppleScript to generate entries straight from BBEdit.