Apparently, hoarding is no longer thought to be a symptom of OCD.
It's still thought to be an anxiety problem - something which is undeniable; I've recently been trying to sort through the possessions of a probable hoarder and she is anxious - but, according to the Daily Mail (yes, I know, but it's the first place the article came up on the internet), hoarding is now thought to be a problem with making decisions, and brain scans show that, when faced with making choices about which belongings to keep and which to give the old heave-ho, people with hoarding problems just can't decide. This, however - in true hoarders - doesn't extend to other people's belongings.
I think I disagree with this. People with OCD have problems with making decisions, and so we - or maybe it's just me? - let OCD make decisions for us. I, for one, have got incredibly lazy: I let my OCD tell me when it's the 'right time' to get up, and when it's the 'right time' to stop brushing my teeth. Some days, my conscious brain has almost stopped making any decisions altogether because OCD-me has taken over.
I imagine that this is how a hoarder feels when faced with the task of getting rid of the rubbish: they don't make a conscious decision based on whether something works, or is useful, or they need it; they just let their hoarding-them take over and make the decision for them.
Maybe hoarding is closer to OCD than scientists have decided?