Julian Assange (Creative Commons)

First, Outside the Beltway explains what the two female complainants are accusing him of:

[Julian] Assange had consensual sex with two women, unbeknownst to one another, who were friends. They had hurt feelings afterwards and confided to a female police officer that Assange had engaged in sex with one of them without a condom, having worn a condom the night before. In the case of the second woman, Assange’s condom broke but he continued to climax, anyway.

You can read the long version with all the dirty details at the Guardian.

Second, there's allegations that his accusers may have ties to the CIA and this whole arrest thing was a set-up to lure Assange into custody. But the Salon summarizes that issue:

The fact is, we just don't know anything right now. Assange may be a rapist, or he may not. His accuser may be a spy or a liar or the heir to Valerie Solanas, or she might be a sexual assault victim who now also gets to enjoy having her name dragged through the mud, or all of the above. The charges against Assange may be retaliation for Cablegate or (cough) they may not.

Though Assange appears headed to Sweden for a possible trial, there's talk the U.S. wants to extradite him and take its own shot at him. The Salon also notes that the process of extraditing him may go on until 2013. 

Even if he is extradited to the U.S., American officials would have a hard time nailing him down for committing a crime, writes the Financial Times.

 The problem for Mr Holder is finding a legal basis to punish the distribution of classified information where the person involved is neither a US official nor the agent of a foreign power.

What is ludicrous is to treat WikiLeaks and its founder as anything better than an agenda-driven group of deceptive megalomaniacs, endangering troops and diplomacy in an attempt to damage the United States and its allies for reasons largely derived from a conspiratorially paranoid view of the world.

Slate takes a different direction with a piece calling Assange a martyr:

Assange's jailing changes the "conversation" from how-dare-he to how-dare-they almost as efficiently as if a deranged vigilante had put a bullet in his brain. Our culture loves to protect and defend "victims," which is what the legal proceedings are turning him into. Overnight, he's becoming an albino Rev. Martin Luther King Jr., writing his letter from jail. He's a pint-sized Solzhenitsyn, fighting for freedom from the gulag. For the impressionable, he's Henry David Thoreau, Nelson Mandela, and Aung San Suu Kyi all wrapped up into one.

Dan Gillmor goes beyond Assange, saying an attack on him is an attack on the First Amendment:

Media organizations with even half a clue need to recognize what is at stake at this point. It's more than immediate self-interest, namely their own ability to do their jobs. It's about the much more important result if they can't. If journalism can routinely be shut down the way the government wants to do this time, we'll have thrown out free speech in this lawless frenzy.