Although possessing marijuana will be legal in both Washington and Oregon come July 1, 2015, it cannot be brought from one state to the other. Transporting marijuana across state lines will still be against the law. This has to do with the fact that possession of marijuana is not legal federally. While the states can choose to legalize the possession of marijuana, these state decisions do not impact the fact that marijuana is illegal for federal purposes.
Additionally, marijuana cannot be shipped to different states, regardless of whether the state has legalized marijuana. Shipping controlled substances such as marijuana is prohibited by federal law.