@Stan_Halen Stan!!! You are finally here!! Man, we have missed you. Your unique take on things is sorely needed. Now we just have to get AJ here...
OK, the thing about this news piece is that the ability to measure ages has seen a significant advance. Warning: this is not straightforward stuff!
Ages are measured using the decay of naturally-occurring radioactive isotopes of a variety of different elements. All elements occur as a range of isotopes (isotopes are versions of the element with different numbers of neutrons but the same number of protons), and some isotopes are stable, and others are not. The unstable ones decay to stable "daughters" at rates that we can measure and that do not change over time. The relevant quantity is the "half life", meaning the time it takes for half the parent to decay to the daughter.
The most commonly known set of isotopes for age-dating are known as "carbon 14" dating. That involves the ratio of carbon-14 to carbon-12. The half-life of that decay scheme is very short, meaning it can be used to measure the ages only of very recent things, which makes it ideal for use in human archeology, for example.
Other element sets have much, much longer half-lives and are great for measuring the ages of ancient materials. Rubidium-strontium, samarium-neodymium, different isotopes of lead, and other systems all can be used this way depending on the ages involved.
The "earlier formation" study has documented an advance in the precision of using a particular analytical technique for measuring isotopic ratios in individual grains of the mineral zircon, ZrSiO4. Like all minerals, it takes up a whole bunch of elements in "trace" quantities, parts per million or even parts per billion levels of concentration. Zircons are special because they can survive billions of years of processing after their initial formation, and still retain the signatures of their original age.
But extracting that information is fiendishly difficult, a huge technical challenge. This team has pushed that ball down the field significantly, and trained the advanced technique on a particular set of rocks collected by Alan Shepard and Ed Mitchell on the Apollo 14 mission. We (as a community) have known for some time that some of these rocks contained tiny grains of zircon, and that if we could just find a way to measure their isotopic compositions, we would have a really important constraint on the age of the Moon.
The BFD about this paper is that they have finally made that breakthrough. And the ages revealed require that enough igneous processing had occurred in order to produce those mineral grains by the age in the paper, which is only some fifty or sixty million years after the very first solids formed in the Solar System from its initial nebula. (Sidebar: we have similar inferences about Mars from study of martian meteorites, that its bulk differentiation -- meaning separation into its primary "layers" of core, mantle, crust -- was complete by no more than 100 million years after time zero.)
Prior to this, we thought that it wasn't until several hundred million years after time zero that the Moon did its thing. So why is this a big deal? Because if the Moon was more or less fully assembled by t=60 m.y., that means it was there to exert gravitational influence on the inner Solar System; and that the processes by which it happened were more rapid than previously thought.
This result is of direct significance to my own research program, which aims to simulate experimentally that process by which the Moon differentiated. We now have to account for all of this happening in less than half the time that we thought before. This is important because there is a range of ages that we know apply to early-formed lunar rocks, especially those that formed the crust, and those have been difficult to reconcile with the model we have for lunar evolution. That model will now need to be revised and adjusted to account for this new observation.
It's a classic case of scientific method. Our interpretations are never perfect, and always subject to revision by new data. However, the "big picture" is still the same, but the details of timing will help us understand not just the Moon but all the rocky, terrestrial planets. Hope that helps!
The second one, that Stan posted, about the multiple-moonlet idea, is less robust. It's mostly speculation, not based on any new measurements or data. I find their arguments rather weak, frankly.
Our next Lunar and Planetary Science Conference will be held in March (and next week I lead the group that sets the scientific program for the meeting) and I am sure there will be some very lively discussion of all of this stuff.