Very very good call. It wasn't seen as masterpiece at the time though; Paul's Boutique has had quite an interesting journey in the history books. I'm going to dig it out for a spin right now.
I understand where you're coming from. For me Let England Shake was a truly wonderful and complete album; the back ground, narrative, songs, art work, every element just seemed to come together in perfection. This is why I thought it stood above all her others.
I have long blathered on about PJ Harvey's Let England Shake as being her high-water-mark and a complete work of art. The down side of such releases comes the realisation that they surely can't top this.....but then she did.
So, which other artists have released a ground breaking, seminal...