Well...the headline only says the planet is 6.9 times as big as Earth. Jupiter is at least that large, last time I checked, so without more context I also don't know what is special about it.
For real. Confirming the existence of any exo planet is a huge technological feat and yet now it's happening non stop. The first ever confirmed exo planet was 1995 and now we've got a catalog of almost 6,000 confirmed. Wild times!
I mean spotting it in only 3 days feels like a pretty big feat in of itself, unless this kid had access to a database on one particular star's brightening and dimming or it's potential weeble wobbling about, he did in 3 days what usually takes weeks at a minimum if it's a planet the size of jupiter or bigger.