It's cute how y'all think that besides Beyonce and Rihanna, anyone is straight friendly.
No one makes a difference between Gaga & Katy.
A straight guy would probably be more embarassed listening to I kissed a girl, Teenage Dream / Firework / Roar type of song, than listening to Poker Face / Just Dance / Paparazzi / Alejandro type of song
Listening to a Pop girl is equally gay, unless the song is something like 7/11 / Pour it Up etc.
But yeah Gaga is the most notorious for the simple reason that she has been the boldest with her support to LGBT.