[This is a re-post from earlier this morning. Technical difficulties.]
Just when you thought it couldn't get any more interesting, Ha'aretz goes and throws this out there: "Archaeologists unearth proof of plot to kill Prophet Jeremiah." Apparently, the discovery of a seal that probably bears a name known from the book of Jeremiah means that the events of Jeremiah 38 are now historically verified in their entirety.
We have a problem here between what the evidence can support and the burden that some would place on it. All the seal does is suggest that a person mentioned in Jeremiah was a real historical person. Despite lingering doubts about connecting the seal with the figure in Jeremiah, it seems highly unlikely that there would be another person with the same name holding a position of power warranting the need for a seal at about the same time. The existence of the Jehucal seal simply strengthens the connection. (Follow the links in earlier posts to comments by Charles Halton and G.M. Grena for background on this line of reasoning.)
The bulla provides another link supporting the assertion that the Bible can be reliably used as a witness to history similarly to any other ancient document. This does not mean that we should conduct archaeology in Israel with a Bible in one hand and a spade in the other - connecting the two with everything we dig up. However, there have been significant finds confirming that the Bible has a pretty good handle on the historical situation, at least in its broad strokes, once we reach the late eighth century. For example, the Siloam tunnel inscription reflects Hezekiah's preparations from his encounter with Sennacherib described in 2 Kings 18-20. The tunnel itself is mentioned in 2 Kings 20:20. Sennacherib's campaign against Judah is especially well-documented by non-biblical sources. His siege and capture of Lachish is recorded in all its gory detail on reliefs from the walls of his palace in Nineveh.
The Gedalyahu bulla does not have nearly the impact of these other finds precisely because it provides so little information. We can't jump from "he's likely a historical person" to "everything connected to him in the Bible is now proven."
[For a list of many of the occurrences of the name "Gedalyahu" in the Bible and epigraphic texts, see the recent post at Abnormal Interests. Thanks to Jim West and Jim Davila for posts that drew my attention to the Ha'aretz story. My apologies for linking to wikipedia for background support. I wouldn't do it if they didn't say what I already knew was true and could document from "real" sources that aren't close at hand right now.]
Update: I just discovered Michael Halcomb's blog with comments on the seal. I completely agree with his assessment of the significance of the find and the problems with the tendency to make too much of the archeology's ability to "prove" the Bible.