Just my personal perception, but:
Julia Gillard was an ineffective communicator and either unclear or disingenuous in her stances. Abbott has always been a mean bastard and upfront about it.
Abbott got in because people couldn't bear any more Labor incompetence, infighting and duplicity. With Abbott, people knew exactly what they would get. Well, now we've got it.
Trouble is, as much as people dislike him, we're once again in a situation like we had with Howard: bastard in power, but no credible opposition.