Yeah, this really, really sucks. I would think that the WiiWare is the answer, but that doesn't really explain why the drought is limited (mostly) to North America.
One possibility that's probably full of holes: Nintendo is concerned about storage space, and they're limiting releases until the issue is resolved one way or another, because they're afraid that if they release too many games while space is limited sales will then suffer (games disappear from the VC new release section after a while, remember, and it's possible that they get a lot of traffic from those links).
As for the NA-only issue, perhaps we tend to download more, and thus have less space per capita than the Europeans or Japanese.
Along the same lines, maybe the think that less competition per week means higher sales for each release? Games stay in the new release section longer, fewer menus to click through, etc.
