First, some details you may or may not know surrounding the new series: Three issues, perfect-bound and larger than the chapters/issues in earlier LoEG volumes, coming out each a year apart. The one just released is set in 1910; the second, due next summer, in 1969; the third, due in 2011, in the present day or not far behind it (right now, as I understand it, planned to be 2009 but susceptible to change).
The stories are intended to be self-contained, but with a through-plot centered on a coming cataclysm (which Moore says will occur in part three). The 1910 fragment includes a seer's visions of one Oliver Haddo, the Aleister Crowley analogue, who will at some point in the future be trying to raise a Moonchild, who will in turn usher in a terrible new aeon of etc.
Now: As always, there is The Text in the Back, telling a parallel story or five. In this case, Minions of the Moon, by "John Thomas" (ho, ho). It starts with a reference to 2001's monolith playing Prometheus for the cavemen, then proceeds to a 1964 mission by Mina Murray to prevent a war between lunar natives from forcing the existing human colonies toward an area off-limits until the turn of the century — unnamed, but given the earlier 2001 reference patently Tycho Crater, and the buried lunar monolith.
Since LoEG has already done the whole Cthulhu thing (all the previous back-page stories have referred to an incident in Arkham involving Mina, Allan Quartermain, and Randolph Carter), I propose that the Moonchild is something different. In fact, I propose to name him, as he will be revealed in either 2010 or 2011 (this is the laying-down-quatloos part):
If he's born in 1969, that would make him 32 by 2001, a reasonable age for an astronaut. And the Starchild, setting off the orbital nukes to prevent their use (and, perhaps, if you include the 2010 plot, turning Jupiter into a second sun), would certainly qualify as a cataclysm that he ushers in.
My marker is down...