It uses the Roku channel store/account API. The names are pulled from the user's Roku account, not the device.
I'm pretty sure it's a private API, but they did add a "Roku API Key" to the developer account page not too long ago. Not sure if it's related, but maybe they're planning on providing access to developers at some point.
My Channels: http://roku.permanence.com - Twitter: @TheEndlessDev
Instant Watch Browser (NetflixIWB), Aquarium Screensaver (AQUARIUM), Clever Clocks Screensaver (CLEVERCLOCKS), iTunes Podcasts (ITPC), My Channels (MYCHANNELS)
