I'm pretty sure the problem is not that they're pleasing fans who aren't me, because occasionally there's something that is squarely aimed at me, and if I notice it in that context, I am still annoyed. And I will make announcements like, "Okay, apparently I am the fan being served here"--which still indicates that I have been thrown out of thinking about the story and into thinking about how the writers interact with their fanbase. Which is not generally a plus while I'm in the middle of experiencing a thing (watching or reading).
So I think that's what's going on there: things that I will object to as pandering or fanservice are things that distort the narrative in favor of hitting certain moments, lines of dialog, or images. And I'm noticing more and more that there are lines of dialog and images that don't suit the current story all that well...but are admirably well-suited for taking out of context in fanvids etc. Which strikes me as sort of equivalent to pausing your song in the middle to throw in a riff that you feel is more sample-able than the rest of the song: I have a problem with derivative works only to the point and in the ways that they interfere with the original. If the awesome riff to sample--or the moment that every fanvidder of your show in the entire world is going to use as a clip--distorts the melody line or the plot line, then we have a problem.
Of course, sometimes I think the problem is that the writers of an ongoing show aren't entirely sure what they want to do with their plot arcs/character relationships, so "distort" is less the problem than "flail around for any solution." I am feeling like the problem with Bones is not just that it's getting more and more pandering with every season* but that in the course of doing so, it's highlighting where I have a different concept of the show than the writers do. I don't actually think the central interesting thing is whether Booth and Brennan end up together romantically; in fact, I don't find that interesting at all. I am not keen on "will they or won't they" plots in the first place, and then they've been so completely transparent about this one that I know the emotional arc of their eventual ending anyway. Brennan has to make some decision that symbolically gives up reason, logic, and data in order to be with Booth, and Booth has to give up nothing in particular to be with Brennan, wheeee. Why am I still watching this? Hodgins sometimes still gets to do experiments. That is why. Sigh.
*In S5, there were three episodes in a row that featured sequences that were only there to show off a male cast member's body in some way. The most egregious of these was when Brennan "had to" take Booth's clothes off him for the purposes of collecting evidence. Honestly. I would not object to more nudity than this show gave me if it was in service of something related to plot and/or character. Rather than practically coming with a squee-track. But this is exactly the sort of thing that 13-year-olds who are not dating come up with. "And then what if Hodgins and Angela were trapped together, like, in an elevator! or on an airplane! or, ooh, I know, in jail!" I have no idea how anyone could look at that and say anything but "fanservice" or "pandering." Unless it was, "Again? Dammit, not again." TV writers! Stop trapping your characters in things! They can interact without being physically forced to, and if they can't, go back and figure out how to write things differently to allow them to do so. Bleh.