Mine's up and working, both the http://player.maniaplanet.com/ and the in-game login are working.
Hope it's working for you guys, too!

I got the same problem, and trying to log in at http://player.maniaplanet.com/ leads to server is taking too long to respond, so yeah I'd too guess it's still a problem with the servers. Let's hope they get it fixed soon... And it'd be nice if Nadeo would acknowledge that they're working on this... ...