Related question: is it bad form to follow someone on academia.edu after you've been formally rejected for a position at their institution? I wouldn't do it while an active candidate for obvious reasons, but it's hard to see how following them after the fact could be construed as a machination (and, in fact, I am just interested in this handy way of following these people's research).
Speaking only for myself, I see no problem with it. I mean, it's not like I expect you to never be allowed to read any of my articles in the
Journal of Underwater Basketweaving just because you once interviewed for a position in my department, so if you like what I do, why not make it easier to find everything?
In fact, I may well follow your research, too (just 'cause you were rejected doesn't mean we don't really like what you do, it just means it wasn't precisely what we needed at the time), though as an attempt at politeness I'd probably give it some time after the search was over to let the sting subside a bit.