Still, they're relying on remote spectrographic evidence (I assume, since Mars Express is an orbital), which has a high degree of error compared to direct sampling.
Beagle would have been able to sample much more directly with a smaller degree of error, but crashed. I'm sure Enterprise mission will blame the aliens / ancient human civilisations / automated defence systems.
Best they can get a probe down there which can actually sample the air with a high degree of accuracy before making wild assumptions that life exists. I have the feeling NASA are only doing this to secure funding for later missions and for PR. I'm not impressed. It may be for the best in the long run, but I'm still not impressed.
