http://nb.wikipedia.org/wiki/Noreg Yes, this does take you to the Norsk (bokmål) article Norge, where you can then click on the interwiki link to Nynorsk (soon probably to be renamed Norsk (nynorsk)) to be taken to the Nynorsk article Noreg. I think this is a relatively minor problem that is outweighed by the general advantages of the drafted solution.
If no: were moved to nb:, I think it would be best for http://nb.wikipedia.org/wiki/Noreg to redirect to http://nb.wikipedia.org/wiki/Norge since it's an nb URL, so people will expect Bokmål.
However, http://no.wikipedia.org/wiki/Noreg would make more sense directing to http://nn.wikipedia.org/wiki/Noreg since if people are looking for Noreg rather than Norge, they're more likely expecting an article in Nynorsk than Bokmål.
It may be possible to start with moving no: to nb: and having all current pages redirect from no: to nb: to prevent breaking any external links to no:, but to leave no: editable so that people can make decisions about whether the no->nb redirect would be better replaced with a no: -> nn redirect. In cases where there was no consensus over where the redirect should go, a disambiguation page could be made. A policy could be created that says the only edits on no: must be redirects or disambiguation page to prevent any new articles being created there.
It sounds to me like some of the people here are taking it for granted that the bokmål community will always stay bigger than the nynorsk community, "so why not just resign and give the bokmål camp exclusive rights to the common language code"?
At the moment, nb is bigger than nn, so it makes sense for no: to redirect to nb, but if we leave open the possibility of creating manual redirects or disambiguation pages at no, this could change over time.
The best argument for creating (not keeping!) a bokmål Wikipedia on "no:" that I have heard so far, came from Lars Alvik:
no: and nn: is right next to each other, compared to nb: and nn:
(nl: in between),
so in a alfabetizied interwikilist, nynorsk and bokmål would get splitted.
Interlanguage links can be put in any order you like. This isn't a technical matter. There have already been discussions on the Hebrew Wikipedia about sorting links by relevance of a language to a topic rather than alphabetically (so the Hebrew page on France would have the fr: interwiki before the others), some Wikipedias prefer to sort by order of local language whilst others do it by order of language code, and a poll on the English Wikipedia showed no consensus on how links should be ordered (http://en.wikipedia.org/wiki/Wikipedia:Language_order_poll ). Therefore, I don't see a reason why there couldn't just be a policy that says nb and nn should be next to each other.
Angela.