According to the Mirror article, there will be a new companion in the TARDIS from next year: "A show insider reveals: 'Martha will still be in Doctor Who, but her relationship with the doctor will have changed. The truth is that she loves him but he doesn't feel the same way. She is going to have to share him because he'll be getting a different sidekick. And this is a major addition to the cast.'"
The article goes on to mention that Martha won't be in every episode next year, but will appear in the occasional episode for both Doctor Who andTorchwood. The item also repeats previous reports that singer Kylie Minoguewill be the (only) companion in this year's Christmas Special.