Microsoft has officially (and quietly) launched the MSN Remote Record feature for all users of Windows XP Media Center Edition to remotely schedule recordings for TV shows. This free service is available currently only in the US and Canada and requires a PC with always-on Internet connection and a Microsoft Passport account. The service has got most (if not all) local cable, satellite and terrestrial channels and their programs covered, and it lets you choose to record either one episode or all for a TV-series. Unless a scheduling conflict arises, which is when it lets you decide what to do.
This service sounds amazingly nice, and I would love to have this feature, whenever I decide to build a proper MCE PC. If you need help setting up Remote Recording on your MCE, then check out the FAQ
here. And, remember to let us know how well it works. ;)