Yes, it will only stream the video/audio signal to the MCE box and won't retrieve any further information. However, tv program information is captured elsewhere via different services. Most people have been using the Zap2it service, but they will no longer be offering this service to the open source community starting September 1st. As a result I suspect most people will switch to Schedules Direct, which the current version of LinuxMCE doesn't yet support (MythTV doesn't support it yet, but close).
Also, if you have multiple outputs on your tuner then you can have one going to your tv and the other going to MCE; that's what was showed in the video. However, it doesn't look your box does support simultaneous outputs to multiple sources, so that option probably won't work with you. Also, that option isn't really used for guide data and such, but rather to get HD quality video output to your TV.