I don't know because I don't live in the "other" region but I suspect that years of having dramatically more expensive hardware (and software) than Japan and North America limited the impact of how expensive the PS3 is; along with this there are certain markets where the more expensive the PS3 is the more attractive it would be to a certain segment of the population.
Much like Japan, Microsoft doesn't really understand the tastes of gamers in many regions within the "Other" region.
Microsoft (to a certain extent) is in an awkward position because it is not seen as either an inexpensive alternative or as the most powerful (or at least most featureful) console on the market; people who want cheap fun will (potentially) choose the Wii and those that want the "best" console may choose the PS3.
Finally, I would say marketing ... Every "XBox 360" advertizement I have seen made for any region is absolute garbage; the XBox 360 does well in North America because its game library and features closely match what the core users of the XBox 360 want.
