Skippern - thanks for mentioning, I am following it. I should have updated here.
Also: there the HackerBus from São Paulo will be in Rio - more info on the thackday list. The tentative plan is to do an OSM workshop on Saturday, June 16 in Complexo do Alemão.
Hey alexz - just seeing your comment now. After a discussion on the tagging list, we're planning on using a closed way tagged
for blocks. Issue right now is that such ways won't show up on OSM.org : p
Amazing attitude, muzito. And... nice work guys: progress is pretty amazing...