Hey, I run OS2007 on my N800 and I _like_ it that way.. it is, to me, a better OS than the alternative (we'll see when Mer comes along, but there will never be an OS2008 on my N800).
As for the forum categories.. to me it's in practice of very little importance, because I, as I suspect many do, just click 'New Posts' when I visit the forum and then I go through threads solely based on the thread subject. The only time I look at the category at all is when the subject doesn't tell me enough - then I glance at the category tag and if it's off-topic I may decide to skip it.