This is what I'm trying to learn about: what is life really like for people who live deep on the west side of Oslo? It's sort of a sociological exploration.
In all seriousness, east vs west is a very common topic of conversation and jokes in Oslo because it's such a segregated city (by both wealth and race). I think it's a pretty interesting topic. Further reading:
Probably too comprehensive Wikipedia
Short article on Oslo's Golden Ghettos
A blog entry
by a French friend of mine with her observations after moving from a basement apartment on the west side (like we do now) to the east side [fixed link]
In Norwegian, but this article
has some striking graphs of differences along a metro line that runs across the city. (On those graphs Majorstuen represents the easternmost west side stop. The graphs are, in order: stops, personal income, % receiving welfare, housing density, % low income, % who do not complete high school, % with higher education).
[tl;dr: west side = more money, east side = less money. neither side is dangerous.]