Other reasons you would want to do this upgrade is so your xbox would play more file formats. My old dashboard would not play .mp4 and .mkv files at all. It would just freeze. This update fixes that problem.
***Important note, if you do not have a back up of your xbox then do so now. Use the xboxhdm file kit and make a boot disk for your xbox so if you ruin your mod then you can rebuild it and no harm will be done. That will only be needed if you loose power during the file copying process not that ruining your xbox is a sure thing but it is nice to have a back up none the less. Also if you have any questions about this or anything pertaining to xbmc for the xbox just let me know and i will clarify as i have already done everything you can for xbmc for xbox and have encountered problems and fixed them. Don't hold me responsible if you mess your xbox up. That being said lets do this.
Step 1: Obtain the Current XBMC Files
This is the URL that will bring you to the most recent build of xbmc for xbox. It is the build i used for this instructable. It is in a .zip file so unzip it and you will find a folder named Build. Only the files inside the folder will be used. The folder contains all the files that will make your xbox into a fully updated xbmc. You can download the apple movie trailers video plugin and any other plugins that you may want from the svn repo installer program once you're done.
Step 2: FTP Time!
Fire up your favorite FTP client program and connect to your xbox. I like to use Filezilla because its free on all platforms so whether you use windows, linux or mac it will work. You should already know how to ftp into your xbox but if you don't the host is your xbox's ip address, the user name is xbox the password is also xbox and the port is 21. Browse to your build folder and transfer all the files inside the folder but not the folder itself to E/Dashboard. When it gives you the option to overwrite the files in E/Dashboard click OK. That's all that is needed so turn your xbox off turn it back on again and it will boot up to the current xbmc build.
If it didn't take then what i do is delete all the files inside of E/Dashboard and then transfer all the files from the build folder into E/Dashboard. Now if you accidentally get a Red Ring of Death and your xbox will no longer boot into anything and tells you that it needs service dont worry. If you have a mod chip installed then you know more about your particular system than i do and im sure you know how to fix this. If you used a softmod on your xbox then youll be fine. All you need to do is stick the game in that you used to mod you xbox, in my case it was the splinter cell game, and get back into your softmod install menu. From there you can FTP back into your xbox hard drive and re transfer the dashboard files. Of course the rrod fix is only for this type of problem and would not work for other RRoD causes. The reason you can fix this is because the xbox which is essentially a Pentium 3 computer has a boot priority of dvd drive first then hard drive. Although i never ran into this RRoD problem when i was updating my dashboard it helps to know how to fix it if it was to happen to you like if your xbox lost power mid transfer and wouldn't reboot.