But it wasn't as if she noticed it; she didn't know it was happening until the Doctor told her about it, and then she complained about it. True, it was Something Important To Know, but it wasn't a new piece of continuity (we'd known about that ability of the TARDIS since Masque of Mandragora). If anything, all it tells us is how much Rose has grown, that coming from a point where she dislikes the idea of the TARDIS messing with her mind, she's willing to try for telepathic communication with the TARDIS in order to convince it to go back to rescue the Doctor.