What Constitutes Blog Spam?

My question then is, is this actually spam?  Spam is generally defined in terms of unsolicited email, or in the blogging world unrelated comments posted to an article that merely are attempts to advertise an unrelated site/product/whatever.  But can the blogs themselves be spam? 

The Merriam-Webster Dictionary defines spam as "unsolicited usually commercial e-mail sent to a large number of addresses"
Even Wikipedia (unbiased, untainted source that it is) when mentioning blog spam specifically limits the definition to email and comments, essentially looking towards directed and unsolicited advertising.
Take a look at the JoeUser/Stardock Terms of Use and you'll see we currently limit the definition of spam to directed, unsolicited emails etc.

But how does that play here on JoeUser?  A site that is very different from typical blog sites, where the emphasis is on community and sharing of articles, instead of everyone being an isolated island disconnected from everyone else on the site.  Sites like Blogger, LiveJournal, Xanga etc do not connect sites together automatically, and there's nothing in the way of automatically showing users an aggregate of recent or popular articles.  So on those sites, advertising blogs vanish into obscurity unless heavily linked to from outside websites.  JoeUser, with it's syndication across all the Stardock sites does all of that automatically.  A single article posted to the Personal Computing section will be crawled by Google from at least three different Stardock sites (JoeUser, GalCiv2, WinCustomize).  And our sites aren't exactly poorly ranked by Alexa or Google, so the spam potential goes way up.

Aside from the auto-linking issues however, does spam need a different definition for sites like JoeUser?  Are these articles even Spam necessarily since they're not unsolicited advertisements?  You don't have to click on them. You don't have to download them.  They don't interfere in any way with your system, your Internet connection or anything critical to your day-to-day life.  They can be annoying, they can push your article out of the "Recent" list, but is that spam?