If we're excluding sales then probably Katy, the bitch has been everywhere for the past year. Her most forgetable single, Teenage Dream, was still hugely popular, everyone knows her singles.
Overall, I vote Gaga, because her dominance cannot be denied. Katy may have 4 #1s, but she hasn't been hugely successful outside the US. Besides, 4 #1 singles and only 1.5M albums sold? Adele has a beast of an album but on the other criteria she cannot overtake Gaga or Rihanna for me.
By far, Katy Perry's "Teenage Dream". How often do you see a 4th single spend 5 weeks at #1 on the Hot 100, and still not achieve its full potential? E.T. could have, and really should have, spent 12 or 13 weeks at #1.
Obviously Katy. I want Rihanna to sabotage all of her promo teams
But I think when It comes to sales wise, Katy = Rihanna.
Katy may sell single beyond amazing, but then she lacks of album sales
While Rihanna may not sell her singles well, but she's sold her album much better than Katy.
Her album is outselling the competition ten fold, with one official single in America and only two worldwide. The only one that can come close...maybe, is Katy. Katy has had a great year in the US, but not ANYWHERE near as good as Adele worldwide, which counts for more
Rihanna's been doing pretty decent, but a couple singles in her popularity seemed to start dwindling (I blame the utter over-exposure around the winter time, when there was far too much Rihanna on the radio due to all her features being released).
Viewing singles as an ongoing representation of the era, Katy utterly dominates. She hasn't been out of the top 10 for a year, she's constantly on the radio. I can't stand her first two singles, but they were still incredibly popular with everyone else.
As for Britney, enh. "Hold It Against Me" didn't seem to catch on very well where I live, but everyone loved Till the World Ends (especially when it came time for a faux "apocalypse" party -.-' ).
Gaga may have exploded onto the scene when she released her album, which sold like hotcakes, but even her era has been shaky, what with the radio turning their back on "Judas" and whatnot.
I haven't been following Adele very much. I know "Rolling in the Deep" was wildly popular on the radio, but I don't even know what her other singles were/are.
