The basic story is that the Abel Beth Maacah excavation has turned up a jar fragment with an inscription on it that reads לבניו (belonging to Benayau). It is written in Hebrew letters and the readings are clear. Epigraphers date it to 900 BCE, give or take. I am not sure whether the script itself identifies the word as "Hebrew" rather than more broadly "Canaanite," but the name is certainly Israelite. It includes a form of the divine name YHWH. It means "YHWH has built." The spelling of the name is specifically Northern Israelite.
As usual with these things, the article tries to draw maximal historical inferences from this discovery. Not a criticism of the author of the article, who seems to be reporting faithfully the views of the archaeologists, with lots of useful background information.
The basic story is quite exciting. Israelite inscriptions, even with just once word, are exceedingly rare in this period. But inferences beyond that basic story are speculative, at least for now.
For some posts on another recent discovery at Abel Beth Maacah, see here and links.
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