A trackback may or may not result in a link to your blog from the blog you’re linking to. At the blogger’s discretion, the trackback link on their post may be allowed to stand or be deleted (or marked as spam).

These links may result in referral traffic, but because they are almost always no-followed, Google does not “see” them when it indexes the blog post. These links pass no PageRank value because they are no-followed. So it depends on why you want the link. If you want it for traffic, it’s reciprocal (but not in a bad way). If you want it to pass PageRank, it’s doesn’t because the trackback link is no-followed. From a PageRank-building perspective, this is not reciprocal.
When you create an in-post link and ping blog services upon publishing your post, that is a pingback to the post you’re linking to. Depending on your blog software, it may show up as a trackback (even though technically it’s a pingback).
This is completely automated in WordPress. Unless a blogger has disabled no-follow, these are NOT crawled by Google.

The only real value of these is traffic. There is no SEO value.

Regarding Reciprocal links: Does a trackback (or pingback for that matter) not result in an actual link on the target blog (i.e. the blog post you are linking to from within your own blog) back to your own blog? Isnt that the point of a trackback - I use a link to reference your post from within one of my own; you get notified of the incoming link, review my post and if you approve of it, a link gets created on your blog, pointing to my blog post?

I’m not clear on how you would create a trackback that is NOT in-post and therefore uses the no-follow rule? I mean, practically speaking, are you not always creating a trackback within a post, and therefore, always receiving a crawled backlink?

One last thing regarding Rob’s question about Reciprocal links: Assuming you are getting non-crawled backlinks (so no SEO value), Trackbacks are still an excellent source of traffic since readers of the blog you linked to may well follow the link back to your blog for further reading…

Cheers,
Carrick

A blogger may choose to use a WordPress plugin that removes “nofollow” from comments and trackbacks/pingbacks separately or both. In this case, it might be possible to see the link as reciprocal.

Serious, thanks for simplifying a somewhat confusing topic. I never really understood the difference between the pingback and trackback, and it seems that basically there is none…good to know.