Here's my conspiracy theory:
1. the gvmt has already made contact with aliens of some kind, or is at least aware of their existence
2. to prevent the release of this information from causing mass hysteria, rioting, and general panic, they are dropping hints about alien life slowly yet continuously to get people more comfortable and accepting of the idea, for example:
> locating exoplanets every week, each more life-supporting than the last
> scientists speculating about cellular-type life on Mars, Europa, Titan, etc etc
> "non-nutters" talking about UFO sightings (Navy guy above, airline pilots, etc)
It's all sort of like the Prime Directive in reverse. I suppose some year we might find out for sure. Hope I am not dead already when it happens.