Personally, I am indifferent. lol
I like holding my tablets in portrait mode more than landscape. I don't like how the buttons are something I have to look out for when I turn it. I also don't like how the tablet doesn't look symetrical anymore.
But I do love the quick access the pysical buttons provide (as others just stated). But I really love the added screen realestate! On my last tablet, it drove me nuts seeing that huge black bar along the bottom with only 3 little buttons on it (and one of them wasn't even the menu button which was randomly placed depending which app you were using).
Either way, I got used to the buttons within a couple days and I (ultimately) prefer them.