I think that the "650,000" emails thing is probably the total number of emails contained on Weiner's device.
This article does a thorough job of explaining the totality of the Clinton email scandal. Skip to number 10 to see information on the most recent developments.
The reporting on this story has been incredibly inconsistent, which is making it really hard to get a handle on exactly what's happening. Part of the fault lies with Comey's letter to Congress - it was really vague and left a lot to interpretation. Part of it lies with congress itself, and more specifically Jason Chaffetz, for shouting to the high heavens that the Clinton email case was "REOPENED!!" when it was never closed in the first place (as
@ThunderHorse pointed out). Yet another part lies with the media's breathless coverage of the event, who took Chaffetz's "Reopened" claim at face value and ran with it. Since then, a number of outlets have had to
retract or significantly walk back their headlines.
Here's the thing: reportedly, these emails were located in a .pst file (or some other form of backup file) on Weiner's computer. FBI officials don't know what are in those emails, as they needed a warrant to examine them (which was obtained today). They learned of the existence of emails related to Clinton by examining the metadata.
Three likely (and one unlikely) scenarios:
1. The emails are part of the group already turned over to the FBI. The scandal is a big wet fart.
2. The emails are not part of the group turned over to the FBI, but were deemed of a "personal nature" and were deleted. Cooking recipes, Chelsea's wedding, etc. Scandal is still a wet fart.
3. The emails are work-related, were not turned over to the FBI, and may or may not contain classified information. Scandal takes on a new life depending on the severity of the information. It's unclear whether or not the FBI will be able to make a thorough review before election day, so if Clinton wins, there could be impeachment proceedings.
4. The emails contain information exposing the entire network of illuminati, space lizards, and satanic cults that drive world affairs. Somewhere out in Texas, Alex Jones takes a sip of his coffee and smiles.