Post updated on 2014/03/10
Reblogging on WordPress.com has a long and contentious history. When it was introduced in June 2010, there was a firestorm of protest by long-standing members of the community against what we felt was an usurpation of our copyrights. At every turn, WordPress.com Staff told us again and again how reblogging was a good thing and that Staff would not take down reblogged material or allow us to disable the Reblog button on our sites.
Fast forward to today, 3 1/2 years later, after the creation of who knows how many WordPress.com splogs whose only purpose was to reblog other people’s content (and maybe include a link to their real site) and we now have the ability to decide whether we wish to allow logged in WordPress.com members to reblog our content or not. Well, almost.
Important Update published! The ability to reblog directly from the WordPress.com Reader means that if you have disabled the Reblog button from appearing on your site, anyone who finds your posts via the Reader will be able to reblog your content.
On the other hand, one aspect of reblogging that has been addressed in the new Reblog is the duplicate content issue. In the comments to the official announcement, Joen A. noted:
A reblog is not a republished post, it’s an excerpt with loads of attribution and links to the original post, including a signal to search engines not to count it as belonging to anyone but the original author.
So that indeed is good news. If someone now reblogs a post from another site, they won’t be getting any search engine juice for it and the original author won’t be penalized.
Currently the Reblog feature appears to take a much larger chunk of text from the original site than it did previously. There was a glitch at the start that took nearly, if not the entire post from the original site, but that was quickly noted by community members and addressed by Staff and we are waiting to return to the shorter excerpt (the current Reblog is around 300 words).
While the new attribution may address the duplicate content issue, it may or may not address legitimate copyright concerns. To reiterate, the Fair Use provision of US Copyright law also states:
The distinction between fair use and infringement may be unclear and not easily defined. There is no specific number of words, lines, or notes that may safely be taken without permission.
Acknowledging the source of the copyrighted material does not substitute for obtaining permission.
As Joen A. also pointed out in his above comment:
So long as copy/paste exists, it’s impossible to prevent users from copying text.
That is so and I do sadly believe that anyone who has intent on reposting someone else’s content will do so, with or without the creator’s permission.
Changing the way Reblog works is a huge step in the right direction. So, while I applaud the move by WordPress.com to give content creators here some control over this built-in utility, what irks is the half-measure of still allowing reblogs from the Reader. If TPTB have already conceded that content creators have a right to control how their creations are used, then let it be done in full.
As always, the information in this post is correct as of publication date. Changes are inevitable.
WPcomMaven 
300 words is way too many – that staff seem intent for large chunks show the staff don’t write much high quality content
Mike-I agree that it is too much, but would rather withhold my judgement until the final shape of the Reblog is set. According to Staff, it’s still a work-in-progress.
“still a work in progress & adjustments are being made” – terrifying words coming from a staff member on Reblog. I guess I am a bit of a cynic on this feature and the staff’s ability on the fine tune.
I think 55 to 70 words are enough. One magazine takes a feed from my site and when I have a good article (most of my stuff) they will put a picture and up to about 70 words from my article on their front page with a link to my original article. I do get some nice traffic when I am on their front page, so they are sort of doing a Reblog.
I have Reblogged a few things on my site and find the number of clicks to the original article to be a low number so I just don’t think the Reblog is the savior for traffic the staff sold it as.
yes you get a bit more exposure than the old copy and paste method since Reblog is way less work and their is a link to your original article that the copy & paste crowd seems to forget the link back.
Thank you for a very clear exposition of the current state of affairs. It occurs to me that while the people at WP may know that the re-blogged post contains signals telling search engines to ignore any attribution except the original author, the reblog spammers may neither know nor care… especially if they are filling a quota at 1,000 re-blogs per dollar.
As for the lack of being able to remove fake/spam followers, this is something that I think is going to move forward rapidly following the latest video from Veritasium about fake followers on Facebook. Have you seen it?
Perhaps if their employers catch on that there is no Google juice gained, they may become redundant. That’s probably wishful thinking.
I haven’t seen the video, David. If you would like to link to it here, please do.
Sometimes I wonder if there isn’t a human sickness in the world incubated and brought about by the rise of the Internet.
Allow me. Eyeopening to say the least!