Its all a fanastic game play by the CIA... Put your paranoid hat on and grab the popcorn.
Contrary to to popular belief, the Americans are not stupid. They can be meticulous in their planning when required (look at NASA). Perhaps they want Assange so badly they have gone for the long, slow and subversive methodology.
The CIA will have already been briefed on the required outcome the US government expects, "at all costs".
Maybe they did create these "trumped up charges" (Maybe Assange dropped himself in it and it was great timing for the US/CIA) to force him from his safe haven, whilst not denying that they will put out an extradition treaty on him if he is sent back. (They won't, but that's not what they want you to think.)
They don't put in an extradition treaty to the UK, their bestest buddies which would be a far simpler legal course of action for them, which strengthens peoples thoughts about the leverage through sweden as the expected course of action.
This is all that most people have been focused on.
He can't go back to Australia (burnt that bridge already, they've disowned him).
Once he's made his choice of next safe haven to jump to, (Equador in this case) the CIA are in a position to get their local agents in position, grease the palms of those in power, bribe and coerce those with influence.
They want a long drawn out process in England. it takes the focus off the clandestine Equadorial CIA staff movements. It gives them the time to set things up the other end.
Once Assange legs it to Equador, there will be massive amounts of media in the UK and descending on Equador for several months.
The heat will die down, the media will grow bored and move on...
And then there will be a swift extradition notice to the Equadorian government and he will be whilsted off, all legal and above board.
So many icons to choose from! The helicopters, the big brother, the joke alert.. I think the choice was right though