EDITED TO ADD: I am getting a lot of links to this. To be clear: WotC is NOT going after OSR blogs or books. They asked 1 author to remove 1 product that had some clear violations of the OGL.
A while back I posted the tales of the OSRIC Player's Guides/References.
The first one I detailed here, http://timbrannan.blogspot.com/2011/09/osric-players-guide-retraction.html
It was just a copy-paste job of the OSRIC rules and some stolen cover art. The author claimed he did not know, which is fine, but then he turned around and did it AGAIN with Holmes Basic producing something called "Mazes & Perils", detailed here, http://theresdungeonsdownunder.blogspot.com/2011/10/ok-ill-keep-blog-open-3-reasons-why.html, http://www.tenkarstavern.com/2011/10/mini-review-mazes-perils-core-rules-osr.html and http://www.tenkarstavern.com/2011/10/fool-me-once-shame-on-you-fool-me-twice.html
Frankly that guy has lost all benefit of the doubt from me.
But that is not the tragedy today.
Today I want to mention the OSRIC Player's Guide, the one detailed here http://timbrannan.blogspot.com/2011/10/other-osric-players-guide.html and here http://underdarkgazette.blogspot.com/2011/10/osric-tale-of-two-players-books-and-no.html
This one was done by the same guy that ran the blog BreeYark!. Unlike the first, this one had been in the works since Jan/Feb of 2011. Unlike the first this one also was full of original art. But like the first one, this one has also been taken down from OneBookShelf and the BreeYark! blog is now gone.
I am not going to speculate as to why. There was a C&D order issued and you can read some more at the K&KA forum, http://www.knights-n-knaves.com/phpbb3/viewtopic.php?f=45&t=8038
I just think it is too bad really that all the work that went into it was lost.
I guess the learning point here is if you are going to publish something and put it up on DriveThru/RPGNow/OBS then you better be sure you know what you are doing. Make sure you understand the OGL (if you are using it), know where your art is coming from. Though I'll admit I thought the OSRIC Player's Guide was fine as far as copyrights/trademarks are concerned. Just goes to show you can't know everything.
I am reminded of something though Clark Peterson of Necromancer Games once said about OSRIC. I won't detail it here, but I am wondering if the eye of Hasbro/WotC is becoming more focused on the OSR. I know they read these blogs, they are gamers afterall. And I am sure that the sales of legit products are nothing compared to what a multi-billion dollar company like Hasbro makes. But all the same we have had some pretty spectacular screw-ups and it might not be long for that attention is on all of us.
I do hope the BreeYark! blog comes back tough.