You've likely gathered all you need to know from this article's headline and didn't even bother to come this far, and I can't say I blame you.
The online servers dedicated to hosting skate.Reel are online, working and available right now! We've tested this amongst ourselves and confirmed it to be true. Further evidence is available from the official skate.reel video upload
section of the website.Edit:
Even though footage and photos can now be uploaded to skate.Reel, the footage can not be viewed through the website. However, players can still link to each other through the game itself, and rate footage through the game. Unfortunately, ratings do not appear to be saving, but we're not sure whether this is a connection issue or a server issue. All that we can recommend is that you try it for yourself.
Fire up that Xbox, pronto! There's no word on how short or long lived this might be.