Well for some reason the comment for cut off...here's the rest:

...married' instead of going out and actually developing a storyline or some user-made quests.

Would be nice to be able to roleplay while doing raids and dungeons, but everyone is go go go go go when it comes to PvE, so I've yet to find people willing to RP that stuff out.

I sometimes wonder if the prevalence of romantic RP is partially due to the built-in amount of dangerous, world-saving storylines in WoW, leaving many players feeling romance is one of the few options left where they sorta have control? Also, it just makes for interesting dynamics and drama.

It's not just lonely singles looking to translate IC romance into OOC hookups, either; I know people in relationships--even married--who end up (intentionally or unintentionally) with characters in relationships due to just how RP itself plays out. it's one of those "just play the character and see what happens" things.

I do dislike the "SOLE SAVIOR AND KILLER OF THE BIG BAD" claims in the guys who sit around being the biggest badass to ever badass; I like being part of the defenders/assault group/was there/etc, but it's an amorphous multi-faction effort.

I've been lucky to find guilds that like to RP and raid together. I've yet to have them not be cool with "hey hold up a sec guys for some RP before this next pull!" Because we all RP as well as PvE; different levels, different amounts, etc, but everyone's cool about it.

Are you talking about how people often RP mundane, ordinary life things (hanging out, relationships, family drama) rather than BIGGER THAN LIFE plot-lines?

LynMars has it pretty much correct, imo. Azeroth is full of enough GRAND stories that it's often difficult, or even tiresome, to make your character a part of big/grandiose plot-lines.

My character is a baker and it's incredibly ordinary -- errands, chores, making deliveries. She has enough "BIG" stuff that she participates in on a regular basis (built-in Azeroth storylines via dailies, raids/dungeons) that it seems more normal for her to just be attempting to live a regular life in the midst of all of that. So, I spend more time focusing on her personal struggles, relationships, etc. That isn't to say that she doesn't participate in BIG storylines when necessary -- it's just not something I seek out. I think that she is an extremely well-rounded, believable character in what is often a larger-than-life world, and I think my focus on "boring/normal" stuff whether it's romantic RP or just daily life RP is what contributes to that.