Moin,
I'd like to say hello, coming over here from Heise:
http://www.heise.de/newsticker/meldung/135887
This project sounds very interesting to me, esp. as I am currently developing an AJAX application that renders OSM data in the browser. :)
Actually I didn't want to announce my project yet, as it is still quite rough and WIP. But I am interested in working with you and hopefully I can offer some insight and help. And in return maybe we can build a faster XAPI server that can return smaller datasets? ;)
As for the actual work, is there more information yet than this mailing list and the talk page:
http://meta.wikimedia.org/wiki/Talk:OpenStreetMap/de
? So far I haven't found much other information.
All the best,
Tels