Center Ice is now available for $129, $30 of the regular price. That offer is good through 10/31 and a free preview will be available for the first week beginning 10/5.
You can call Comcast direct to order but if you get a CSR who doesn't know what you are talking about, ask for someone who does.
update 6:48pm, Jim, a reader from the Philadelphia area just commented the same package is available there too. I would think Center Ice for cable subscribers in North America is now available or will be soon.
CI for satellite has been available for a couple of weeks.