Nitpicking here but, it's not exciting the photons, it's exciting the electrons in the fluorophores, which as they relax emit a photon of a different wavelength. It also says that they are using two photon microscopy which basically requires the energy from two simultaneous photon interactions with the electron to excite it to the required energy level, so yes the fluorescent probes are necessary.
This will also retain the problems that the article claims to remove, namely the damaging of the cells and photobleaching (exciting the fluorophore to a point where it is no longer fluorescent) because light of the same wavelength as previous techniques is still needed to excite the fluorophore and so is still being applied to the cell. The only benefit in this regard is that (probably) less light is applied, so the effects will take longer to appear.
Slashdot Mirror
Nitpicking here but, it's not exciting the photons, it's exciting the electrons in the fluorophores, which as they relax emit a photon of a different wavelength. It also says that they are using two photon microscopy which basically requires the energy from two simultaneous photon interactions with the electron to excite it to the required energy level, so yes the fluorescent probes are necessary. This will also retain the problems that the article claims to remove, namely the damaging of the cells and photobleaching (exciting the fluorophore to a point where it is no longer fluorescent) because light of the same wavelength as previous techniques is still needed to excite the fluorophore and so is still being applied to the cell. The only benefit in this regard is that (probably) less light is applied, so the effects will take longer to appear.