At least four. Soosoo Toys just anounced their "Speedsilver"...or Figuremasters. I think it's great for collectors/fans of the X-men that we have 3 companies making these figures lots of choice, lots of characters.
And there is also a DOFP "weather manipulator" from Five Star upcoming, but I don't like the cheap look of the sculpt, although the costume is not that bad. (But I don't like DOFP Storm in general, even if it was the only Storm we would get, which would be a pity.)