If the producers of AI were truly interested in correcting the voting problems, they would do one of two things:
A - Limit the number of votes per household. This would probably be the most fair, as it would stop the mass-dialing crowd from having so much of an impact. It would also have the benefit of minimizing the effectiveness of the VFTW type of juvenile people (and I'm being as nice as I can) that want to ruin the show for everyone else.
B - Change the vote from who you want to stay to who you want to go. That way, someone like Brenna would never last (or Scott Savol from last year). Again, this would balance out the mass-dialers somewhat, as even a mass dialing could not save a contestant that performed really badly (everyone else would be voting for the same person). Also, it throws it in the face of the juveniles at that other site, as they would then have to consciously make the decision to vote the best singer out of the competition, rather than just trying to keep the talentless hacks they promote from being kicked out.
The best choice is probably just to limit the number of votes per household, but that's not likely to happen. They enjoy touting those millions of votes too much to change things.