As a straight female who hangs with straight men... the only popstars that I've heard being discussed are Rihanna and Beyonce. A guy I used to talk to (white guy, age 26) went out and bought Unapologetic during it's release week.
My usual social circle consists of Kappas (who are often on the DL so you have to take it with a grain of salt) and other fraternity members, a few basketball players, some football players, and some straight up weed heads who are doing enough just to get by in college. They bop to songs like Pour It Up, Drunk In Love, Jump, Stay, Partition, Rocket, etc. I've never heard their asses mention the other girls except for as a joke.
Actually... we were listening to the radio one day and Dark Horse came on and one of my male friends were saying "yo this is lowkey kind of fire" and the other two guys that were at my apt just gave him a look and he laughed and was like "I mean the beat goes and Juicy J kind of went in" and they were like nah Juicy's verse is beat and the only thing good about the song is the beat.
The "straight guys love my fav!!!" discussion is so dumb.
I'm pretty sure they're not speaking at length about the type of music homos listen to, or trying to use it as proof of their favorite artist's popularity.