Just as a counter to that, on the mobile version of the site she does have her own banner, just not with the artwork picture next to it, since the artwork for her, Robin and Captain Falcon is the same one and is on Robin's page. Also, the Smash Bros. Facebook page had her own 'challenger approaching' picture. So I think that argument is just a result of poor website formatting rather than her not being a 'true newcomer'.
That said, having seen the video she is almost certainly a Marth clone, which is disappointing. But Robin is hype enough for me to ignore that.
And as for the Gematsu leak, it does make me worried for Shulk's chances, though I won't be shedding any tears for the Chorus Men.