Some people erroneously believe that if it’s been published on the Internet, it’s in the public domain. For the vast majority of works, including blog posts and web sites, this is simply not true. Even if a work does not carry a copyright notice, either the standard one or a license under Creative Commons (or something of that nature), and even if it’s not formally registered, it still falls under the protection of federal (and likely international) copyright laws.
The only exceptions to this are things like government web sites and publications (because the government is a public entity, its publications are always in the public domain) and works where the copyright protection has lapsed, such as many of the older books that have been digitized by Google, etc. Even still, common practice and standards in genealogy dictate that these should be appropriately attributed.
Let’s be frank, folks: Copying someone else’s work without proper attribution is plagiarism, regardless of whether or not a work is protected by copyright or license.
It’s unethical, if not outright illegal, to take someone else’s work and pass it off as one’s own. And when someone blatantly plagiarizes another person’s work, the solution is not to ignore it or titter behind one’s hand, like school children on a playground, but to bring this infraction to the public’s attention in a manner that is calm and rational.
Me? No one could accuse me of possessing either trait. My first reaction is always to go in with fists flying. (Or maybe cast iron pans. Hey, whatever’s handy.) Hmm. That must be the Scots-Irish in me…