Just head up to the regular https://www.google.com/adsense/ web site, and if you're using a supported mobile device (like iPhones or Androids), you'll be greated with a new and improved mobile version.
If you still prefer to use the regular web interface, you can switch back and forth easily whenever you feel like it.
Looks like a lot of people will be staring at their mobile device's screens even more from now on (as if they didn't do that enough already! :)
