^ Perhaps related to the news that it's apparently to be upgraded to a Class B drug soon? So they've got lotsa pics to show off their sterling work in defeating those naughty drug dealers to the media when it's announced. As with all "big pushes" in the pathetic WoD, they'll soon give up and move on to the next media hot potato. Hopefully.
Yeah, mainly a psychological addiction although it can be just as destructive and all-consuming as any other addiction. Crack is also "only" psychologically addictive but that doesn't mean it's somehow a "lesser" addiction. There is a minor physical element as it is, after all, an anaesthetic so the body does adapt to an anaesthetised state which can lead to some physical w/d symptoms. They are fairly minor though and it is predominantly the psychological aspect that's the real problem.
As to comparing it to coke or meth (again, both psychological dependencies) how long is a piece of string? Totally depends on the individual. It's pretty damn addictive though. Or at least it certainly has potential to be. I know I've lost more than one friend to ketamine addiction and all that goes with it.