Hei Carlos!
The NorWord course is good, I started with it, too. For me, Norwegian is quite easy and I'd say it shouldn't be too difficult for you either. There's only one form for each tense of a verb. But there are quite a lot of irregular verbs.
Nynorsk is not spoken in Oslo, they speak Bokmål there. But here's an article about it:
"Nynorsk
Nynorsk is one of the two variants of Norwegian language, and is used by 10-15 percent of the population. This language is supposed to represent the Norwegian dialects, and is thus more open to lexical diversity and flexibility than bokmål (Book Language), also when used in radio and television. Nynorsk is mostly used in western Norway and in the valleys of southern Norway. In the heavily populated areas around Oslo, nynorsk is normally not used, as in northern Norway, most towns, in business life etc. For many Norwegians, nynorsk is rural and oldfashioned. Bokmål has a geographical and social centre (in Oslo, in the upper class etc), nynorsk does not have this. In stead, institutions like the schools, the church, and NRK - the Norwegian Broacasting Corporation - are important scenes for the use of nynorsk.
Nynorsk vs bokmål
Bokmål is the dominating variant of Norwegian, and the norm for spoken bokmål is quite close to the dialects of Oslo. Although pupils are never taught to speak either bokmål or nynorsk in Norwegian schools, the Oslo dialect(s) and spoken bokmål is very common in Norway and quite easy for many to use. The users of bokmål in radio and television have probably a quite clear impression of correct/acceptable/incorrect, suitable/unsuitable etc in the spoken version of their written language. Their norm is also prestigeous and quite stable.
The opposite can in many cases be said about nynorsk. But media usage is important for the nynorsk language, especially in radio and television, where nobody can "avoid" the often unpopular nynorsk. The nynorsk users do have their clear role models in radio and television, but the written nynorsk is quite open to lexical variety - and also variation in the way of spelling words. Further, this manifold is reflected in the oral usage of the language. It is many ways of speaking nynorsk, the norm is not stable. This fact makes it possible to track influence and loyality in the construction of the spoken version of nynorsk. "
Source:
http://www.geocities.com/Athens/Academy ... ritten.htm
In general one can say that Norwegians speak their local dialect, but write Nynorsk or Bokmål.