@raincoaster: I am a law student and know extensively about the DMCA process. The issue of spammy reblogs should be solved technically at WordPress.com with a simple switch disabling reblogs, or with a more finer grained solution enabling the original poster to remove his content from the offending WordPress.com page, not via a DMCA process too cumbersome for most content owners to care. If I have to go through the hoops of a DMCA process I might as well take my blog away from WordPress.com.
In my opinion there is no value added other than the revenue generated from the display of extra ads (which incidentally benefits only WordPress.com / Automattic) when a parasite reblogs my content, as opposed to a legitimate writer who pings back from her own original blog, citing excerpts and elaborating further with her own original ideas adding to the conversation.
In that sense WordPress.com is not doing what it is licensed to do, namely to "display, distribute and promote my blog". Reblogs demote my blog in that they promote the blog of the reblogger where it is in competition with mine; reblogs distribute the reblogger blog where it is in competition with mine; reblogs display the reblogger's blog where mine would have been displayed legitimately instead.
I trust that Google is not stupid and will find a way around the reblogs spam. So will legitimate bloggers. WordPress.com can be part of the problem (as it seems to be now) or part of the solution (if it gives control to the owner of the original post to allow or disallow reblogs and to edit likes and ). My experience of WordPress.com in recent times is that it has become increasingly part of the spam problem. "Likes", "reblogs", and "follows" are all nice idea with legitimate purposes, but the way they are implemented at WordPress.com they are open for abuse by self-promoting spammers.