I'm thinking the lack of buzz about the Grados might be due, in part, to the fact that the PS1000s are inherently "workman-like" phones. That is, they're not beautiful, though they still look very nice, but they are functional to the max. The metal cups will definitely get nicked up, and you just accept that as part of the deal. But they will be the kind of phones you will be reaching for over the long run, I would think.
It could also be because they're a little pricier than the Sennheiser HD800s, and that they're being released much more slowly. That and the fact that Sennheiser can afford to run a much more extensive publicity campaign for what I have to insist are a great product. The Grado PS1000s just seem to be more like "home brew" cans - and I don't meant that in a negative sense. They're incredibly solid, but I'd hesitate to call them "sexy."
I know the HD800s as well, and they're, like I said, really great too - I love the velvety feel to the pads and the great soundstage, and the sound in general. To me, they're perfection, in a sense (I know, I've read the posts about 6 khz spikes, complaints that they lack sufficient lower end - though I don't have this impression myself). The one thing the HD800s lack that the Grados have is that hands' on, made in the garage feel that the Grados seem to have. It's almost like, "hey, Grado just patched together a better mouse trap."
That's all a long, and inarticulate way of saying that you can go to a very expensive elegant (but not stuffy) restaurant with all of the trappings, great food, candlelight, nice clother, etc. and that's what the HD800s feel like. You can even go to the same restaurant dress down for lunch and that's also the Senns. Gotta love that. BUT. you can also go to an equally pricey, but much more rustical (okay, "hole in the wall") restaurant that, despite its lack of elegant exterior, and its being located a little off the beaten path, where the food is equally great - but different - and still say it was worth the price. To me, that's what the PS1000s feel like. Both are really great phones, and both complement each other very nicely.