Yeah I just discovered it and am finding it quite useful. Sometimes I need to reference my collection so this is really easy (once you sit down and enter everything!)
I also find it's interesting to see what some of the records are supposedly worth. And it's good for finding stuff to buy.. cheaper than eBay from what i've seen, but I haven't bought anything yet.. got my eye on a few things, but I've already filled my record buying quota for this month (or this year more like it!)