In terms of the basics, then, the My Book World Edition is pretty good. It looks nice, is easy to setup, and has all the basic functionality you'd hope for. However, what sets this apart from the rest of the NAS box fraternity is its extras. Included with each box is Western Digital's Anywhere Backup software, which has five licenses, and the box can be accessed via Mionet's remote access service.
Starting with the backup software, this is a constant-monitor backup service so once you've made your initial backup the software keeps an eye on all the files and folders and checks when you've made an update, deleted something or moved it. If you do change something, the software will then invisibly kick in and add an incremental update to the original backup. By default, three versions (the original and two updates) of a file will be kept before the original is replaced, and if you delete a file the two previous versions will still be available. It is incredibly easy to setup and although the initial backup takes sometime, subsequent backups impact little on everyday use.
As for the remote access service, well, you can ignore it if you know how to set up remote access manually on NAS appliances but for your average user it can all be a bit much. Mionet, then, is an online service that makes this process really easy. It's normally for use with your home PC and all you do is download and install a piece of software. So long as you then leave your PC on, you can access it remotely. With the My Book World Edition, Western Digital has embedded this installation into the NAS box itself. In other words, not only are all your files now accessible from any PC in your home, they're now accessible from anywhere round the world.
This, combined with the backup software and the 1TB version's competitive price, puts the My Book World Edition a cut above the rest of the NAS box masses, especially for the novice home user. If you're an advanced user you may want to opt for a different appliance which lets you install your own software (bittorrent client, anyone?). Also, if you're a business user we'd recommend stumping up the money and buying a proper RAID NAS box to ensure your data is safe.
Western Digital's My Book World Edition doesn't necessarily bring anything brand new to the NAS box market but for the novice user it's an ideal entry-level appliance. It's easy to set up, includes decent backup software and an easy to use remote access service, and the price is right too.