In short, I have turned comments off on this website.
Since the middle of our brief sojourn in the 21st century, social media has exploded. Facebook has peaked (by which I mean, of course, my use of it has peaked), Twitter is still on the rise (by which I mean, my use is continuing to increase). Overall we may have passed Peak Blog (although we just may be in the Trough of Disillusionment).
Many people read this blog from an RSS feed (usually Google reader or some frontend for Google reader: I use Reeder on the iPhone and PerfectRSS on the iPad and Google Reader on my computers).
Others see posts on Twitter. Some actually come to the blog website itself. A very small fraction post comments. A slightly larger fraction see them (those who click to comment themselves, or come to the blog via Twitter, but not those who read it on RSS or even the website, since unless you are sharing the post, or explicitly want to read comments, there is no reason to click through to the page). I wish everyone would just use RSS to read links and we could be done with it. But that is not the world we live in.
Most of the few comments were useful. A small fraction of prospective commenters also complain to me the commenting system is painful or broken. This blog is a MoveableType blog administered by the University of Minnesota UThink service, so I have very little control over the system. Authentication is aimed to reduce spammers, which it does at the cost of annoying non-spammers (Security is the enemy of efficiency).
The Transportationist was never really intended to be a community, though of course it has its partisans. I am not making a living off my blog (or from book sales) so I have not done much in the way of SEO or attempting to drive traffic. My blogging earns no academic credit, it does not appear on my CV, and is probably viewed by colleagues as a distraction or waste of time. At best it earns me fame, at worst, infamy. Given the number of readers (which can be measured in Micro-Grubers), I doubt either is the case. I doubt I got any research projects funded due to blogging. My views are eclectic on the conventional political axes, and so no one is really sure if I am on their team.
Where else I write:

• Books (and Wikibooks) [In engineering, Books earn almost no academic credit. You should read (and write) them anyway.]

• Articles and Reports – Typically in peer reviewed journals, at conferences, or working papers, linked to on my website.

• Streets.MN – Approximately biweekly, approximately 1000 words, approximately on something transportation-land use related in Minnesota.

• Twitter – Public, but short, usually for links … this is where the energy on Linklists has gone. Some have noted that there are a lot less linklists than before. This was about a 1 year experiment. I know it was relatively popular, but the effort was high, higher than it should be due to the wrong tools. In particular, if I read on an iPad, it is a pain to share a link via the blog (my workflow entailed emailing it to myself, loading the link on my desktop, sending that to the blog), but quite easy via Twitter. Since much of my blog reading has migrated to 5:00 am in bed on an iPad, this is how it has worked out. Twitter also gets a twitterfeed from my blog, since by definition, everything I write here I think is link list worthy.
  There are also a slew of other blogs (TransportationNation, The Other Side of the Tracks, Autoblog, Politico: Morning Transportation, etc.) that do similar link lists (I know a few follow me), so my value-added here is fairly low, maybe catching an interesting article or promoting a story earlier than it otherwise would be. They are paid for this, I am not.
  Anyway, if you like my curation of links, follow me on Twitter. The reason I do this is mainly for my future reference rather than what I think others are interested in, but if you are interested in some of what I am interested in, it will work for you.
  

• Emails (one to one or one to few conversations). I try to keep these as brief as possible. In some cases, down to a single letter (Y, N). If you don’t ask an explicit question requiring a response, you may not get a response.

And then there are the Other Social Networks:

1. Facebook. I used to automatically feed my blog here, but it stopped. I just it started again with Twitterfeed. I assume most people will ignore or block me. I occasionally comment on someone’s post, or like something. I don’t know why. I occasionally post pictures of the kids, but I am torn between that and Flickr, and lately Flickr gets more love. If I know you in real life, feel free to FB me.

• LinkedIn. I still don’t know what it is for, but I have lots of contacts. I don’t write here and stopped feeding the blog here when they had some technical issues (posting a picture of Jenny McCarthy with my post). I just started again with Twitterfeed, since there are a few readers there. Feel free to Contact me there.

• GooglePlus. I send my posts to Google+. I don’t know why, though there are a few readers there. Feel free to Encircle me there.

The Transportationist dates from April 2006 (notably post-tenure). So what is the purpose of The Transportationist: It is temporally random, featuring posts of random length but almost always less than 5000 words and often less than 500, generally something transportation-land use related or an announcement of something I or my students have written or edited elsewhere, or a conference, or a talk, etc. In short it is my and my research group’s blog (but I am solely responsible for its content). It is not a community website, or intended for comments generally (in contrast with e.g. Streets.MN), though some posts in the past have drawn quite a few. If you think what the blog says is interesting, follow it. If not, keep calm and carry on.
If you have comments, you should get a blog (or if you have one, post there). As someone on the web remarked, that will get a lot more attention for both of us due to Google’s PageRank formula than posting on comments with a nofollow tag. If you think I should post something, feel free to email me, I sometimes posts “A reader writes” type of posts, or “A reader responds”. Let me know if you prefer anonymity from the rest of the world, but I still need to know who you are.
Another complaint about comments. I don’t much like anonymous speech (though I understand the need in the case of totalitarian dictatorships, that is not the situation here). Most comments are anonymous. If I ever migrate to a new platform, I will reconsider. As someone said, never read the bottom half of the internet. Also don’t feed the trolls.
If you want to get in touch with me, there are lots of channels, frankly too many. Email is probably best. You are smart, you can find it.
So if you are still with me, thanks for reading to the end of the post.