Originally Posted by sebbbi
The replay system just records your button presses. To simulate the button presses you need to run the game physics engine, and to have all the 3d physics models (of all tracks) loaded to your phone's memory. To render the replay graphics, you would need to have the full graphics engine of the game running on your phone, and to have all the 3d graphics models (of all game tracks) loaded to phone's memory. Basically if we had the replay viewer that could show a fully accurate replay based on your button presses, we could just allow you to input the button presses yourself on the phone and play the full game. The first problem is... there's no phone currently that even had enough memory to load all the Trials HD graphics & physics models to it... the second is, no phone is powerful enough to run Trials HD using exactly the same physics quality (a requirement for the replay system to work properly)... and third, no phone can access the Xbox Live leaderboards directly (except for the Microsoft Windows Phone).
It's technically possible to get high score data (not replays) from the leaderboards to a web server (some retail games have done this), so we could theoretically show some leaderboard data in our website, and have app to download that to a phone. However I don't think we could make specific real time queries for your personal data. Something like top 100 global ranking lists at our website is likely technically possible, but I don't think we would be able release a title update just for that. It's however a nice idea to keep in mind for our future projects.