I imagine its not too high. Perhaps in the 800mw range, anything above that could risk the diode's life time (this is important considering how this is supposed to be used every night). It looks like it couldn't be more then a watt, and it seems to be closer to half a watt of output, judging by the beam and spot brightness. It's hard to tell, though, and every camera picks up 445nm differently.
AAlasers