Re GUI config for radio - I would envision a page with the same layout as all the other pages structurally, but where the top header has back, stop, play, forward, we could add a pause button (so that rune notes the position of the currently selected audiofile and resumes it when that button is hit again) for general purpose use.
While in FM mode, the play button could act as an unmute, the stop button as a mute, the previous button/next button to scan left/right (if we can implement that). The bottom header would remain unchanged of course.
Middle pane - View 1 - Would have a number of presets, anywhere from 3-10 I guess? Treat them as buttons like the standard webkit does. Make it configurable. Quick and easy way for someone to program in their favourite stations and probably the quickest to implement if that command line thing is anything to go by. This would be my preferred goal in beta software to simply get it working inside the RuneUI.
Middle pane - View 2- Would have an option to do a scan, where the unit scans the frequencies (and lets say, 88Mhz to 108mhz) then analyze the peaks vs the troughs and report the frequency of those spikes as a menuitem. The user could specify their own frequencies from the beginning to the end of whatever their particular dongle supports. The one we have does 80mhz to 1700mhz and in some cases further than that if you make some upconverter hardware. (And can also do AM radio if you make one of these too).
Middle pane - View 3 - would be an interactive slider with a scale, so one could use their finger on a touchscreen to slide from 88-108mhz with definition up to 1/10th of a mhz - 1/10th of a mhz is also what I would recommend as being the scan interval for View 2.
This would fit in with the schema that Rune already has, with the header and footer being permanently visible and controlling the most important stuff, with the middle pane configurable for whatever the user wants to do.
The scary thing with SDR is that you can literally pick up anything radio related with this hardware and software. Police scanners. Mobile phone traffic. International Space Station. Airplane transponders. Once the interface is implemented, I can see some of the RTL-SDR fanboys getting involved, as it would open up that hobby set to people that need to have a flashable image rather than doing a build process. The hardware costs $10 and the software is there in the form of open source code...
I'm currently documenting my build for my Pi-Fi and will publish in a separate thread. I'm not sure about widgets and webkit, but if in the radio 'view' itd be cool if the gui could display a frequency strength gauge/meter, as that will vary second to second depending on atmospherics.
And Im imagining within the 'radio' view there would be the ability to select initially between FM, DAB and perhaps later on, AM, Shortwave, others? Would be super neat if you could listen to live CB radio, but I'm getting way ahead of myself. FM would be the first goal, but DAB the main goal. Any others would be cool.
And there was a guy here offering his services as a graphic designer. Could perhaps use him to design background images for the frequency selection overlay.
-D
EDIT- Alternatively, you could use the playback screen to select the input via the MPD button that already exists, but make the left hand 'progress' meter morph into a tuning dial. That would be really funky...