Destructoid has posted a rumor that the first batch of DLC will include Julius and Maria as playable characters, as well as a pyramid level based on the Egyptian levels in Portrait of Ruin. It looks pretty convincing. Interestingly, it looks as though Julius will be able to swing from those metallic things that're usually reserved for use with Shanoa's magnetic ring (whatever the Hell it's called), similar to how Simon Belmont could in IV. 
 
Bear in mind that - based on the screenshots - these do appear to be separate DLC items. I'm hoping that characters aren't more than 80 MSP.

Well, now we know why a six player game only had five playable characters. 

That piece of shit game is getting DLC? I bet its a 200kb unlock.

" That piece of shit game is getting DLC? I bet its a 200kb unlock. "

For my $15 bucks, I've already gotten my monies worth of this game at about 15+ hours of enjoyment and will continue to love it for a long while, so I'm way into DLC.  Hope it's reasonably priced, and by that I mean I hope it doesn't throw my MS point total off of multiples of 400, haha.
 
BTW, oh man, the article mentions Grant Danasty.  I never even thought about him!  How would wall climbing effect the current game?  I wouldn't think it would be too breaking.  Most of the bosses (excepting the first one) have a full radius of fuck up zone.
 
The possibilities...  I really hope they don't stop expanding this game for a long time.  The foundation is there to add as many new characters (and especially chapters!) as they want.

Here's some game play of Julius in action: 
 
http://www.zshare.net/video/790685681cff7979/

With how bad this game's lobby system is, i'm kind of scared that you'll buy the dlc level and never be able to use it because someone joined your team that didn't buy it.

I heard the Download will be 4 megs. so I imagine your getting new sprite art and not unlocking previously downloaded assets.  i hope....

I would hope that it's a required 4meg update, and then you pay to unlock it so people without the dlc can play with them, this game does not need a player devide on dlc vs no dlc.