yeah, it transfers automatically if you are on a single ticket. i think though, if you are on two tickets you gotta transfer it yourself. when it will get there is something else. although some people claim they have "always" gotten their bag upon arrival, i think the numbers are more like 98%, or some such. on transfers with 2 hrs plus between flights, i think we have averaged about that 98%. on the iad-fra-blq with a legal 45min or so transfer, we average about 50%.

that lost bag does not necessarily show up an hour later. in both lhr and led, the bags arrived 3 days later.