The new LEGO Passenger Train set is now available from Shop at Home for customers in the US, priced at $129.99 USD and with 669 elements.
This set makes use of the Power Functions transmitter and receiver. The engine is powered by a 6-AAA battery pack in roughly the same form factor as the more-expensive lithium-ion battery. It will be interesting to see what sort of run-time (or lack thereof) is available from the 6-AAA pack.
Also available is the Train Station, $49.99 USD and 361 pieces. We're still waiting on the Cargo Train and Track Crane / Crossing sets to become available in the US.