Every interface should not just look good, but also feels right, making your experience flawlessly intuitive and simple.
WordPress.com is the only service of its kind that not only lets you export your data, but gives you an open source package you can run on pretty much any web host out there to run your own instance of the software. So the freedom is really in your hands.
Using different devices in various situations should be an advantage, not a drawback. And I like advantages.