For me, it’s not about ease of use. I’ve written a basic blogging app and some other PHP/MySQL from scratch. I also have options through my institution. For example, I wanted to use a closed microblogging space with some of my classes this semester, and was able to set up a locally hosted StatusNet instance in a couple of hours.
Rather than being about self expression, I think personal cyberinfrastructure is about control. Noiseprofessor points out the value of paying for hosting, rather than being a data point. While that’s a good thing, Amazon’s recent declaration of Wikileaks as persona non grata points up that paying for your own hosting gets you only so much. If you really want freedom, do you in fact need your own plugin server (as Eben Moglen has suggested) and perhaps an alternative network not controlled by large corporations (Mark Pesce has written about the idea of distributed DNS over HTTP). Short of that, what does paying for hosting from a large hosting corporation give you that you wouldn’t get from having a good backup?
There is the issue of identity consistency. Having your own domain strengthens your ability to “create a brand” (see Bon Stewart’s post). Does that make setting up your own host worth it? I haven’t decided yet.