Sorry, my previous tree had a flattened layout. Here's the right one:
xwiki-platform
==============
/svnroot/xwiki/xwiki-platform/
|_ core for now
|_ xwiki-model, xwiki-storage etc. in the future
|_ webapp
|_ gwt
|_ standard
|_ xwiki-platform-ui (the components below may be moved to the
component level in the future, i.e. would be at the same level as
xwiki-model etc.)
|_ eclipse-ui
|_ flex-ui
|_ xul-ui
|_ web-ui-standard
|_ templates
|_ skins
|_ gwt
|_ plugins: only the platform core plugins: image, packaging,
fileupload, zipexplorer, but not: flickr, graphviz, ...
xwiki-applications
==================
/svnroot/xwiki/xwiki-applications/
|_ xwiki-blog
|_ wiki
|_ xwiki-calendar
|_ plugins/
|_ com.xpn.xwiki.plugins.CalendarPlugin
|_ wiki/
|_ xwiki-enterprise-manager
|_ wiki
|_ web
|_ distribution
|_ xwiki-watch
|_ xwiki-concerto
|_ ...
Stéphane