For all those who may be taking this lightly, we shouldn't discount the seriousness of this virus simply because we are seeing it so soon in its life. The speed of modern communication has somewhat unfortunately caused many of us to be cynical.
Yes, this new one has already picked up genetic segments, apparently from exposure in pigs, that makes it better at surviving and reproducing in mammalian (including human) respiratory tracts. They’ve never seen these gene segments in this type of avian flu outbreak in humans.
All influenzas are thought to originate in birds. The problem when a new influenza emerges is that our immune systems have never seen it before, so it takes longer to mount an immune response and the disease becomes more severe. Another problem can be that the immune system (the innate system that is always there, not the antibody system) overreacts, causing a "cytokine storm" that kills. The cytokine storms are thought to be the major factor in why so many people died when the H1N1 virus first emerged, back in 1918. Now, almost a century later, H1N1 is not nearly as lethal. Even "typical" influenzas can have a fairly high death rate--but are still pretty mild when compared to the 1918 flu.