I doubt they will bring Barrowman back. Firstly, I doubt he will find romm in his schedual between the fantastic four reboot trilogy (also hear that there was a FF and spider-man cross over, and that he was appearing in the new marvel zombies film) and I doubt they will think of a decent way to bring him back, especialy after they killed him so horrificly. Also I've hear rumours that series 7 will be the last torchwood, it's not the same since Rex took over. It's creepy that they kept Eve on for so long though, she's going grey now, and her kid is a horny teenager now. Ha, renember when Gwens kid slept with Rex?
Also, I've hear rumours that they will bring the doctor back for his fourteenth incarnation, and that Justin Timberlake will be the new one. The second American doctor!