I've added now a first version of my planned realtime charting on the status page in the 'Query statistics'-Tab (click on "Realtime chart"). You can check it out at http://demo.phpmyadmin.net/gsoc-tyron
Currently it aggregates the average queries per second by making an ajax request every 2-2.5 seconds (2 seconds + time for one ajax request). Since it is using the differential of the status var 'questions' it takes some seconds to display a line.
For the chart I'm currently using Highcharts because it allows realtime data, animates beautifully, is really small (1 file, 77kb minified) and has a export to png/pdf/jpg plugin (6.4kb minified) which however uses a highcharts.com server for the conversion.
Some radical suggestion in this regard: What about removing the included pChart and instead using a client-side charting library? I know for some part its bad since a student wrote a whole lot of code for it just last year, but looking at some requirements for phpmyadmin (no file storage, limited possibilities for data recording, panning/zooming, realtime updates) a server-side charting library offers much less possibilities compared to a client side-one. And if we'd use highcharts it would save us like 16 files and 750kb (well most of it is that dejavu font). I think it would be pretty easy to replace actually. Instead of the graph, the server-code would just need to send the already generated chart data hidden in the document and then we add a bit of js code to display the chart. Some code from chart.lib.php is probably reusable.
Please let me know what you think and whether I should continue working in this direction. Thanks! :)