I'm glad to see this thread! One of the pros if I get accepted for a Ph.D. will be the ability to finally co-habitate with my sweetie! He's currently in Denver and I'm in Los Angeles. In the past we've both applied for jobs in each others' cities and gotten fairly far but never offered positions. So when I decided last year to apply to do a Ph.D., it was pretty obvious I'd need to move (Denver doesn't offer a Ph.D. in my subject and the only program local to me is at a school I prefer to not attend).
I was only going to apply to Seattle, which was a place my sweetie was okay relocating to--there are lots of jobs offered in his field, and in the meantime he's also started a distance master's program out of UW (as a side note, he's the one who convinced me to do the MLIS a few years ago, and after I finished, I convinced him; that's the program he's in now), so he could either continue online or try to transfer into the in-person program. When speaking with the professor I knew at UW, she suggested two other programs to me that were closely in line with my specific research interests: Milwaukee and Urbana-Champaign. My sweetie made it clear that he would not go to Urbana-Champaign, but when I asked him how he felt about Milwaukee (I thought he'd be dead-set against it), he replied: "Well, there's a lot of Frank Lloyd Wright houses in Wisconsin I'd like to see." So that was that, and I applied to the two schools.
We've talked a bit about what we might do and where we might go after the Ph.D., and how to figure that out. And while we're keeping our options open, we both have places where we know we *don't* want to live, so that determines a lot of where we plan on looking for positions and jobs. Also, if I want to teach info science, there are a limited number of universities that are not in our 'no fly zones', so that helps us focus our searches.