The Tragedy of Macbeth (Act 1)

I enjoy Shakespeare's writing style, though his tragedies can be very depressing (obviously). The speech in the plays is very elegant, and though the old English may take more time to interpret, I find it well worth the effort. He is usually very detailed in his writing, and his descriptions are very thorough. In Macbeth, specifically, he begins the play quickly with conversation. The plot advances rapidly from that point. Macbeth seems to have been written at a faster pace than, say, Frankenstein.

Thus far, Irish captains under king Duncan, Macbeth and Banquo, have defeated Norwegian rebels. The thane (lord) of Cawdor has been killed, and Duncan declares that Macbeth will be the new thane of Cawdor. Meanwhile, Macbeth and Banquo meet three witches, who say  Macbeth will be thane of Cawdor and later king, and that Banquo's children will be kings. Macbeth is then told by those under Duncan that he is now the thane of Cawdor, so he assumes - and desires - to be king. However, Duncan announces his eldest son as his successor. When Duncan comes to visit Macbeth at his castle, Lady Macbeth convinces her husband that they should kill the king.
As I mentioned, the plot seems to be progressing faster than some of Shakespeare's other works. Shakespeare already diffuses some suspense as to the truth of the three witches' words when Macbeth is declared thane of Cawdor. Yet, the majority of the action is yet to come, as this being a tragedy, we know that the murder of the king cannot bring good to Macbeth. Also, Shakespeare is subtle in the upset of Macbeth's plans, as the scene in which the king declares his son his successor is brief. The entire plot is ominous.

Plays offer a different type of characterization, as the only option is to use indirect characterization. Shakespeare uses dialogue to tell about the actions and traits of the characters, and I believe this gives the reader a more in-depth idea of the characters' personalities.
Macbeth apparently suffers a major personality change. He was a loyal and "valiant" captain, a seemingly close friend to Banquo, and described by his wife as being too kind. Yet when tempted with the possibility of power, he becomes greedy and violent.
Banquo seems to be a mild person, who is wise and cautious as portrayed by how he warns Macbeth not to trust the witches.
From the readers' perspective, King Duncan seems to be good-natured and a just king, but ignorant and too trusting. This may result from the fact that we know Macbeth's intentions, but he doesn't.
Lady Macbeth, from the first scene she appears in, is shown to be manipulative and selfish. She seems to have little guilt for evil acts. For a woman in that time period, Shakespeare gives her a surprising amount of power, because she was the one who first gave Macbeth the idea of killing the king and greatly influences his decisions.