She (the actress) is hot and went on to play a prostitute.
That unfortunately plays into that whole thing as well to some people.
On a more personal level I like Rose a lot more than, say, Martha, because she got the ball rolling again, Rose being the first person we focus on in rejuvenated Who. She's funny and brilliant, I love her accent and she was awesome as Bad Puppy Rose. She does the whole conscience of the doctor'-thing very well, especially in the first season as a companion to PTSD Doctor.