I personally think the Mafia storyline has legs to last another 8 months or so. Now your reaction to that would probably be "WHAT??? Your dumb" but while I think they will probably end it soon, I think it should continue and I'll tell you why.
Kurt Angle needs the mafia now. Without it, he is just Kurt Angle heel again. The Mafia disbanding for good leaves him back to where he was in summer of 2008, without the title and without a real purpose other than feuding with AJ. Kurt Angle the character wouldn't let the Mafia go down that easy.
Booker T and Steiner, for all intents and purposes, are probably, or should, be written out of the picture. Whether it be disappearing, a beatdown or whatever. They need to go.
That leaves, Kurt Angle, Kevin Nash and Samoa Joe left. Like Angle, Nash is lost without the Mafia. Useless. Joe can go back and be the nation of violence again, but I think there needs to be more to it than that. All 3 guys aren't going anywhere, unless Angle is REALLY leaving TNA. If Angle leaves, then the Mafia should die, but with Angle, the Mafia should live.
Now, the Mafia would need members and former world champions to be those members. Mick Foley, Rhino, Abyss, Bobby Lashley and Jeff Jarrett are the only world champs left in TNA besides the Mafia and AJ Styles (who should NEVER join).
Rhino makes sense because he is a heel and is feuding with the same people. Mick Foley would make sense because he just turned heel. Abyss could turn heel, but that's rather anti-climatic now with recent developments. Bobby and Jeff are ruled out for obvious reasons, though Lashley could work, there is just too much money to be made with him as a face.
So... what would the new Mafia do? Well... they would be a typical stable. I personally, would rather TV time dedicate to a group like the Mafia then the individuals themselves spread throughout the show. It is a good idea to conglomerate your talent like this in order to save TV time.
This... all leading to Lethal Lockdown in April where the TNA Frontline battle the Main Event Mafia. The frontline wins, the Mafia disbands itself just by Angle and Nash blaming everyone else for the loss. From there, the story follows each member as Angle throws the blame around at Nash and Joe. The feuds from that run till BFG2010.
That way, the front line get the big Lockdown win, the Mafia gimmick is played out to its full potential, making use of guys like Rhino and Foley. The storyline wouldn't always be the center of attention as it has been for 12 months now, but it would work on its own terms to give Angle an entourage.
Face it, Angle has had a team since he turned heel. First Team Angle, Angle Alliance then the Main Event Mafia. He will again, and you might as well call it the MEM. Even as an excuse to sell more T-shirts and to use the trademark that they have been advertising for a year straight. The trademark MAIN EVENT MAFIA is still worth another 6 months or so.
This is how the nWo should have ended. The nWo should have ended with them imploding with egos after a big War Games loss to WCW. The feuds from that would lead to Starrcade (ala Bound For Glory). It buys time for the company to figure out what they are doing next.
Like the nWo was for WCW, the Main Event Mafia is an establishment within TNA that has been marketed and sold to the public for 12 months. T-shirts, posters, hats, collectors items and other things were branded with the logo and the name in order to get the name out. It's a brand in its own. Just like Suicide is a brand for TNA or DX is a brand for WWE. Those brands make money for the promotion. Kurt Angle, Bobby Lashley, Christian, John Cena, Randy Orton, CM Punk can jump ship, but brands such as DX, Suicide, Undertaker, Main Event Mafia, nWo can never leave the company that created them, which is why they are worth more.