[OSM-newbies] river not rendering

[Aspen Swartz]

I'm tracing out the Amur river from Yahoo imagery.  There is a section
that isn't rendering, and I can't figure out why.  You can see the
whole missing section here at zoom 10
http://www.openstreetmap.org/?lat=52.818&lon=139.896&zoom=10&layers=B000FTF
although the islands don't show up, making it look like a bigger river
than it is.

The other sections of the river (that are mapped so far) render all
the way from zoom 6.

Then it appears at zoom 11:
http://www.openstreetmap.org/?lat=52.898&lon=139.715&zoom=11&layers=B000FTF

I know this is a rendering thing, not a mapping thing, but I copied
the tags for that section of the river directly from the downstream
section that someone else mapped before me, that renders correctly,
just adding a multipolygon relation for the islands.  So I'm afraid
I'm doing something wrong.  Or is it just a matter of time before that
part shows up?  Anyone have an idea?

Thanks,
Aspen (eulochon)