Continental has long been a partner with Alaska Airlines, along with most Skyteam and oneworld carriers. Their partnership wasn’t as tight as Northwest’s and Delta’s, flights between the partners did not earn elite qualifying miles.
Alaska’s model has been to partner with basically everyone who wasn’t partnering with United, the carrier’s primary competition (other than Southwest) up and down the West Coast of the U.S.
And since Continental is leaving Skyteam and partnering up with Star Alliance and United, the Continental-Alaska partnership is coming to an end. The last day is October 24, 2009.
Of course, within a few days of that Continental flying will be able to be credited to United (or any Star Alliance program) and vice versa.