The "Is this a good laptop for Ubuntu" questions are definitely offtopic I think unless someone is asking for a specific issue along the lines of "I am interested in a Dell Latitude X123 but it has this specific wireless card and all the information on the internet seems to indicate that it's problematic, does anyone know if this is supported in Ubuntu?" or something like that.
As far as the "sort of wiki" questions I'm not so sure. I don't think for example that the Thinkpad Edge thread will end up being as thorough and as maintained as thinkwiki or attract as many experts as say the thinkpad-linux mailing list.
On the other hand from my experience on working with the Ubuntu wiki for my current laptop is that people tend to not update wiki documentation even though they can. I've seen a few questions where people here link to the wiki docs and then in their answer say "the wiki is out of date so do this instead" but then no one goes and fixes the wiki!
I personally would love to have my laptop page be on Ask instead because the user experience is so much faster/better (the Ubuntu wiki is slow and painful to use). However I am hesitant to do so because we should really be improving the official documentation -- which means the wiki.
However people tend to make HOWTO threads on their laptops anyway regardless of what the official docs say so I figure you might as well use better tools.
I think we should watch the thinkpad edge and shuttle threads over the next few weeks to see if they can be useful -- if they end up awesome then we should allow them, if they end up junk then we can drop it.