You might recall that I reviewed the Edge back in April. One feature that made me really happy was that it could export your annotations as a PDF. It was the only ereader with that ability at the time. I do wonder if Sony added this export in response to my post. I don't know if they did, but I do know that I can't find it in the PRS-600 user manual, and that ereader had largely the same feature set as the 650.
Update: a commenter pointed out that I was wrong; the PRS-600 could export notes. I'll take his word for it; I just went through the manual again and I can't see where this feature is mentioned. #SonyFAIL
You'll need the Sony Reader Library software to extract the notes, and you'll get a RTF file.The RTF file will have highlighted excerpts, typed notes, and whatever you scribbled on the screen.
Unfortunately, this doesn't work all that well. It's difficult to get the screen shots out; I'd much rather have a PDF. But I think part of my problem with the screen shot is that it appears to be acting like it is an SVG, and I don't know how to handle it. Also, Mike Cane noted some time back that DRM breaks the export feature. If you highlight part of a DRM protected ebook; it won't get exported. And Sony hid the export button quite well (they can't design a user interface to save their lives).
All in all, this is a good start and it's better than anything the Nook, Kobo, or Pocketbook can do. If you were wondering why Sony charged more, this is a pretty good reason.
Second Update: Now that we know that Sony added this feature last year, it changes my perception. It really should work better by now.