Why do people think Nintendo's E3 plans will slip by under the radar of the mainstream E3 audience? Their meetings, Nintendo Directs, and show floor demos will still be very much a part of E3 festivities. Whatever sites the primary E3 audience uses to follow E3 events will still be covering Nintendo news. The amount of coverage Nintendo receives won't be affected by the format they choose -- rather than showing everything they have in a single hour-or-so-long conference, they'll split it up a bit over the course of a few days.
It's not like the folks over at IGN or Destructoid are going to see the next Smash Bros reveal and say, "gee, maybe this would be worth drawing attention to if it had been revealed during a live press conference in a huge room. Since it was only shown off in a Nintendo Direct, no one will care about Super Smash Bros, so there's no point reporting on it."