With both the Firehose and the "New Discussion System", the layout is borked with a large grey box. This is apparently because the "intended" page width is wider than the available space (as the problem does not exhibit itself on 1280x1024).
On 1280x1024, the Firehose feed/feedback links run over the right-hand summary bar.
OS: WinXP SP2
See attached screenshot for example.