I agree about Lorde- I already liked Royals and then I heard Team and it was even better. She's great.
Most of the "currently popular" songs I like are from last year.
Like Radioactive by Imagine Dragons. And Pompeii by Bastille. And Ain't It Fun by Paramore. I still hear them on the radio quite often so I guess it counts. I can't remember anything from this year that I really enjoy, but I know there has to be some.
EDIT- I forgot to add Counting Stars by Onerepublic... One of the best songs to become popular recently in my opinion. And Best Day of My Life by whoever does it... I love that song!