Well... first, neutrinos apparently have no mass. Thus, they are not bound to the same limits of particles containing mass, which would require an infinite amount of energy to accelerate up to
c (speed of light in vacuum). So nothing extraordinary about it
reaching c.
For it to go superluminal is something else, though. In theory, anything traveling at
c (a photon) wouldn't experience time - as
c is the reference frame, it's like time doesn't pass - but faster than
c would possibly mean going
back in time! But because neutrinos have no mass, I don't know if that qualifies for
faster than light communication (
Faster-than-light - Wikipedia, the free encyclopedia). In other words, if it really means time travel.
Also, given they are detecting neutrinos traveling thru +700km of underground, I wouldn't be surprised if they travel faster than light
in vacuum. Materials with different refraction indexes are known to cause some waves to travel faster than
c, so maybe analog phenomena could happen for neutrinos while traveling thru mass.