Holmes in the books is a drug-addicted eccentric (self-described "Bohemian") who lives in incredible mess and at the service of what seems much like manic cycles, including irregular sleeping and eating habits.
He also consorts with the dregs of society (the irregulars) and is fully capable of flat out action hero stuff when the story asks for it. He habitually lies to the police, has no aversion whatsoever to the finer points of breaking and entering, and can be quite a jerk when establishing that he is smarter than someone else. This is not far off from the trailer at all.
They removed the cold fish aspect of his personality to make him more likable. A change, yes, but not one I'm going to hang them for. Seeing how much of a showman he was in front of Watson of the police, the cold fish thing was either eccentricity or a straight up act, anyway. Yet, for some reason, that is the only aspect of his personality we have reliably seen on screen.
They extended his messiness to include personal hygiene. Gamers shouldn't be throwing stones about this.
And I think it's common to forget that the character was also a boxer in the books. Oh, look... that was in the trailer, too.
Oh, and they made him actually interested in sex, apparently. Heavens forfend that a drug addicted manic depressive should also be interested in sex.