Lately, DC Comics has gone in two different direction with the original Captain Marvel. In the main DC Universe, they have decided to totally re-imagine the character, at least in part to differentiate him from Superman. Since the beginning these two characters have been at loggerheads. Both of them are super-strong, invulnerable, and can fly, and are the greatest heroes in their respective universes. When they wound up in the same universe, a logical question was “what do you need to have both heroes for, when each of them can do pretty much what the other one can?”
The answer, for DC Comics, has recently been to play on one key difference between the two: Superman was a science fiction concept: an alien from outer space with powers far beyond those of mortal man. Captain Marvel was a product of magic: a hero with the abilities of a half-dozen mythological and legendary characters.
In the ongoing trend of having a mighty, company-wide crossover event every year to drive collector and fan excitement about the company, as well as, yet again, “cleaning up” some of the messiness in the DC Universe left over since the last big “clean up the DC Universe” event, Zero Hour, DC Comics brought forth Infinite Crisis.
In the lead up to this event, Days of Vengeance, the magical element of Captain Marvel was brought to the fore. Captain Marvel was used as a focus of all the magic in the universe, as every magical character focused their energy on the Captain so he could grow in stature to battle the Spectre, a magical, god-like being that had, ironically, been created by Jerry Siegel back in 1939. He wound up losing the fight, though. Also in the story, old Shazam died and the Rock of Eternity was destroyed.
By the end of the Infinite Crisis, it was established that there were now 52 parallel universes. The “post Crisis on Infinite Earths” universe remains, and most of the old DC Universes (Earths 1, 2, 3, etc) seem to have been recreated, as well as self-contained universes for the characters of each company that they have acquired (Earths S, X, etc.). This now allows DC Comics to create stories with the characters in their original universes, if they ever choose to do so.
The Rock of Eternity had been rebuilt, and Billy Batson was installed there to keep an eye on the magical world, as the Rules of Magic have been “rewritten.” In other words, Captain Marvel became the top cop for magical monsters and demons. Before that could be explored further, however, something happened. Billy Batson said “Shazam” one day and the Captain Marvel he transformed into was different. He was in a white version of the Marvel suit, his hair was long, straight, and white, and his cape was long and had a hood. He looked like Elric of Melniboné, Michael Moorcock's magical albino, on steroids! At the same time, Captain Marvel Jr. and Mary Marvel both instantly lost their powers!
It turns out that Billy Batson/Captain Marvel is now to sit on the throne of Shazam. Billy Batson looks to never be seen again, and the character simply uses the name “Marvel.”
Freddy Freeman, the Shazam Family outsider, and former Outsider (since losing his powers) has been set on a quest to earn each individual power of Shazam (Solomon's wisdom, Hercules' strength, Achilles' courage, etc.) in a series of trials chronicled in the recent series Trials of Shazam. One result of these trials is that the hero who will ultimately say the magic word and wear the red suit with the gold lightning bolt (Freddy Freeman) will be called Shazam. Dan Didio, editor-in-chief of DC Comics has admitted that part of the reason for this is to finally have a comic book with the character who's name is the same as the title.
Mary Batson, after recovering from injuries sustained when she lost her powers, fell into a fit of depression, sought to regain her powers, and met Black Adam. He gave her back access to the Power of Shazam, but also a share of his powers. This made her more powerful and and gave her a greater range of use of magic, and she gained a new costume, a black, long-sleeved, capeless number with a very short skirt.. Once the moral center of the Shazam Family, she fell to the temptations of that power, almost becoming a tool of the villain Eclipso. She overcame that temptation, however, when she realized that she was being used, and lost her powers again. She regained her original powers (and a new white costume with long sleeves and a gray lightning bolt) when she realized that what she really wanted was to help people with her powers. Then the villain Darkseid tempted her with the powers that she had gained from Black Adam and debates of moral relativism, and Mary accepted them, and the black costume reappeared.