I'm inclined to think that the author is not doing anything malicious, the js code is obscured/minified so it's hard to verify that. I'll say that the analytics script has the sole purpose of tracking real usage (the webstore doesn't provide any info on "active" installs).
Other than this, the author already received a comment pointing out the existence of readability, i hope he'll update his code soon.
Ok, the author confirms with a webstore comment that none of this data come from the users. It looks like they test the extension on various websites and add there manually the text location for sites that are not being parsed correctly...