What more is there to say? Man of Steel looks very interesting from these teasers. However... I don't believe a man can fly... yet. We'll see if that's changed when the full length trailer hits. There isn't much difference between the trailers, except from the voice-over, which features both Kal-El and Clark Kent's father figures.
This one features Kevin Costner as Jonathan Kent.
And this one features Russell Crowe as Jor-El.
Is it exciting enough? No, not yet, but I think this is just the first in a long line of hype peices which will build up that excitement until I am bursting for Superman to return. In the meantime, I think I'll go back to watching the incredible blu-ray collection. Man of Steel has Superman 1 and 2 (Donner cut) to live up to, and that's a pretty hefty task.