Amanda Knox Heads Home

A smiling Amanda Knox was spotted traveling home today, her first day of freedom after being acquitted of the murder of roommate Meredith Kercher in Italy. INSIDE EDITION reports.

Amanda Knox was all smiles on her first full day of freedom as she began her 6,000-mile journey home.

The 24-year-old college student, who spent the last four years in an Italian prison, was expected back in the United States Tuesday night.

CBS's Peter Van Sant reported, "Amanda Knox left prison in a Mercedes sedan with blackened windows. They made their way to Rome, where this morning the family boarded a flight."

She seemed almost giddy as she passed through security at Leonardo Da Vinci airport in Rome to fly to London.

Her happy smile of freedom is a stark contrast to her flood of tears after learning she would be released from prison.  

In an open letter to her supporters, Knox said: "Many shared my pain and helped me to survive on hope. Those who wrote to me, who defended me, who stayed close to me, who prayed for me. We are forever grateful. I love you, Amanda."

A passenger on the same flight spoke to Fox News by phone: "She looked great, she did not look tired, she looked very well rested, she looked happy. The sisters were all just smiles having a good time and they were all changing seats to sit next to Amanda."

In London, Knox was given the full VIP treatment. A van waited for her on the tarmac and she was kept away from other passengers.

Then it was time to board a flight to her home town of Seattle, ready to pick of the pieces of her life and start over.   

But there is anger in Italy over her release. The crowd outside court in Perugia jeered the verdict.

"The crowd that I was surrounded by, they were chanting, 'Shame! Shame! Shame!' They were very angry. It was a bit frightening to be in the midst of that, frankly. In that moment, people here were disgusted with the verdict," Van Sant said.

A headline in an Italian newspaper asks, "If not Amanda, then who?"

In Britain, home of murder victim Meredith Kercher, tabloids called Knox "Foxy Knoxy," and scoffed at the verdict, saying she is free to make a fortune from book and movie deals.

In the U.S., Bill O'Reilly compared Knox to Casey Anthony:

"None of us knows exactly what happened in those situations, and we have to depend on a flawed justice system, whether it's here in the USA or in Italy, to define things for us," he said.

Backstage at Dancing with the Stars, former prosecutor Nancy Grace was also skeptical.

"I had predicted that the Italian justice system would think Amanda Knox was just too cute for jail and that's exactly what happened," she said.

Knox's former boyfriend Raffaele Sollecito is also free, but the heavy toll of life behind bars is etched on his face. He says he wants to immigrate to Canada and start over.

"They never turned on one another. This is almost a Romeo and Juliet story in a way. They protected one other throughout. There were offers, particularly to Raffaele's side, and if [he] would only testify against Amanda Knox, they'd reduce his sentence. He never agreed to do that," said Van Sant.

Knox may not be out of the woods. The Italian prosecutor has said he will appeal her acquittal. If Italy's high court overturns the decision, prosecutors could request that Knox be extradited back to Italy. However, most observes think that is highly unlikely.