I didn't know I'm supposed to switch off the RSS footer before doing so, hence every imported post contains my RSS feed's footer. I'm also wondering how much havoc will this wreak on search engine ranking, but we'll see.
Importing itself was tricky; apparently WordPress people don't maintain the publicly available Blogger import plugin as much as they should. The one installed on their hosted service, WordPress.com, sports both importing by authenticating with your data, as well as allowing you to upload exported Blogger data.
Publicly available plugin allows only importing by authentication… which fails. I've attempted to import from a subfolder on my ivan.vucica.net domain (while waiting for the DNS people to switch the entry for the blog.vucica.net hostname). That is, I've installed into http://ivan.vucica.net/wp/ and I can only guess that this is what is causing Google's AuthSub service to raise hands in disgust and give up.
On the other hand, WordPress.com not only manages to log me in (possibly because http://ivucica.wordpress.com/ is not a subfolder), but it would allow me to upload the data exported from Blogger.
All in all, Blogger people did their work superbly, as did WordPress.com people… WordPress.org people did not. Let's hope publicly available plugin does not become abandonware, for the sake of future importers. Otherwise, people will have to create temporary blogs on WordPress.com, import from Blogger, and then import into their local installations. And having to do two imports sucks.