What does Hamlet's soliloquy in Act 1 reveal about his state of mind?

In this soliloquy we get to really hear Hamlet's thoughts
for the first time in the play.  We already know from the previous scene that Hamlet is
still in deep mourning for his dead father, but we learn a lot more about all of this
from this speech.

He opens with a comment about he feels
dirty (sullied) by his association with the royal throne of Denmark.  He is specifically
talking about his disgust for his mother's quick marriage to Claudius.  He regards this
marriage as incestuous and is outraged that his mother, who was so dearly loved by his
father, should move on with a man who is NOTHING like his father.  He even compares the
two men as "Hyperion to a satyr."  He ends the speech with a specific comment about the
"wicked speed" with which she went "to incestuous
sheets."

In other parts of the speech he comments on his
contemplation of suicide, but notes that it is against the God's laws, which reveals
another aspect of Hamlet's morality.

Hamlet sees Denmark
and the world as miserable hopeless places.  There is such abject sadness in his
observation of "how weary, stale, flat, and unprofitable, seem to me all the uses of
this world!"  Hamlet is clearly in a depressed state of
mind!!

The speech as a whole is so interesting because
Hamlet vaccilates between deep, dark depression and outright anger.  This contrast will
be with him throughout the entire play.