The Planet, one of the biggest server renting companies around has confirmed that it doesn't have K10 quad core AMD processors listed and that it doesn't plan to add them to its portfolio any time soon.
A company sales representative said that Kentsfield is the better way to go and they recommend Intel to anyone who wants more than two cores.
It is still unknown when these guys will have K10 based machines to offer, but it doesn't look that bright at least not on the short term.