Personally, I was quite surprised about Backpage.com being shut down. It always seemed, to me, to be just a less useful version of Craig's List. It was obvious that there were no real personals on the site. They were all just escort posts and nothing of interest to me.
The troubling thing is that any government entity can shut down any website after a self-defined classification of the content. It's a dangerous precedent. It's also worth noting that legislation allowing sites to be charged if others use the site for sexual abuse has caused Craig's List to shut down their Personals section.