The post actually linked to a Greasemonkey script that displayed music lyrics next to the YouTube player. In fact, the script doesn't even work right now, probably because the author hasn't updated it since 2009.
I've sent a counter notice to Google and here's the answer I've received:
We have received and reviewed your DMCA counter notice. At this time, Google has decided not to take action based on our policies concerning content removal and reinstatement. We encourage you to review http://www.educause.edu/library/digital-millennium-copyright-act-dmca for more information about the DMCA.
I understand that it's now illegal to link to infringing content, but I don't see why that script infringed Inspection 12's copyright. The script obtained lyrics from sites like lyricwiki.org, songmeanings.net, metrolyrics.com, which license lyrics from Gracenote and LyricFind. Some of these sites have APIs, so Greasemonkey scripts could use their lyrics. Since 2008, when I wrote that post, many lyrics sites started to license content, just like Google's YouTube did.
Another issue is that all the claims from the DMCA notice are inaccurate and show that Inspection 12's representatives didn't even visit my blog.
Does this mean I now have to delete all the posts about lyrics sites and plug-ins? Am I allowed to link to lyrics sites? Is it OK to send bogus DMCA notices to Google and remove any page that links to lyrics sites and plug-ins?
Update: Part 3 and Part 4.