I doubt it is more evidence of microbiological life forms, we have already got evidence from those asteroids that originated from Mars. Releasing notes saying hey we have discovered more is hardly going to change the way we think in our search for ET life.
I also doubt that NASA are finally going to admit to contact with other species, so what the release is, IS hopefully going to be interesting. Personally I think we are being slowly introduced to the idea of alien visitation, NASA doing this, the UN looking to appoint an ambassador to alien affairs, all the current growth in sightings etc, makes me feel like were being spoon fed BS so that we don't react badly when ships are eventually flying over every major city