If you care about the authority of your site's content, then it's a bad thing.
If you know that you can't stop this type of
spblogging and they happen to
use your content - with links back to your site from your content - don't count
it as a total loss. Why? Their PR gives you "link love".
I have been used this way on some of my blogs, and following the trackbacks,
I see that my content is on their sites - but just a snip (like an RSS feed type
of link - which as "more here..." that links to my site).
What I do, and recommend you all do as well, is link your articles and posts back
to pages on your site. For example, if you post about "red widgets" - and have a
"red widgets" page on your site, then you would link that keyword in your post to
your page on that site.
There is a wordpress plugin that links keywords on your site to any URL you specify
in your admin + options tab for that plugin. So, you link every instance of "red widget"
to a page on that site, and it'll automatically generate (valid HTML) anchor tags for it.
Every post I have seen of mine on a splog, I see my backlinks as well
If you can't beat 'em, make 'em work for you!
