Although kernel team (and the rest of the development team) specifically don't want to commit to supporting VirtualBox, the practical fact is that a lot of people like to run Fedora in VirtualBox, and we don't at present have formal testing in place to find out if it's actually working during release validation.

In practice, we usually find out about any bugs via people trying it and then posting their results to test@ or the forums, but this is pretty rough and ready and it's easy to lose the information. If we add formal VBox testing to the release validation process we'll probably find out about VBox fails sooner and do a better job of tracking them for possible fixes or at least documentation at release time.

So, ideally, we should write test cases for deploying Fedora as a VBox guest (and possibly using it as a VBox host), and add these to the installation validation matrix as 'advisory' tests (tests not associated with Alpha, Beta or Final release phases, and without a corresponding release criterion).

Dan Mashal, who I hope I've added to CC, is interested in this topic and may choose to be an awesome rock star and contribute the test cases