Answer: BLiG – a fast-growing, Portuguese language blog platform powered by WordPress MU (naturally).
The site itself is a pretty massive undertaking. Spread over a cluster of servers, it offers pretty much everything you could want in a large blogging platform — and a little bit extra.
Alongside features like global tags, users can also post by email (a custom feature not available in standard WPMU installations), offer blog subscriptions to their readers, track their stats via an integrated statistics engine based on Piwik, and post podcasts with remarkable ease.
And to make the login process seamless, blog creation is entirely integrated with the iG authentication bus.
Finally, users get a special treat of more than 40 themes, custom made for the site. These can be edited almost every which way in terms of layout, color, font, header, and more.
All in all, it’s fantástico :) It’s great to see WordPress MU adopted by such a huge player in the Brazilian internet space!