Cell phone radiation is typically in the GHz wave range, and rTMS, as well as most brain waves, typically between 1 and 30 Hz. They are completely different parts of the spectrum, well, so unless you are a pigeon, I don't think there's much effect.
I have no concerns about cell phone radiation but I'd just like to point out that the high carrier frequencies don't necessarily preclude effects on low frequency systems. The modulation envelope probably extends down quite close to DC (think about the modulation induced by a cell phone adapting its emission to towers) and virtually any non-linear circuit can act as a rectifier/detector. I used to work in an accelerator physics lab and the low frequency effects of RF leaks could be interesting.
I wonder what effect the 60 cycle radiation from the power mains has on people? Presumably not much, or there would be some evidence with such a large number of people being constantly exposed. And yet TMS at 30 hz apparently has a huge effect. I feel like I am missing some piece of the picture here. Perhaps it's the intensity that makes the difference.
Were they ever? Cellphones have been shown to heat the side of you brain. No evidence that it alters its functioning though. Going out in the sun also heats the side of you brain.