The Wall Street Journal has some very interesting details about the Marvel Studios/Sony Pictures Spider-Man deal, and they reveal that it was still dead as of December. Obviously that rumoured "Spidey Summit" in January changed things, and Marvel will now have to scramble to make some changes to Captain America: Civil War as the site has heard from their studio insiders that it is indeed the movie which Spider-Man will first appear in (which was obvious, but not guaranteed at such a late stage).
As for Sinister Six, they add that while it will no longer be released next November, "The studio will rethink its approach to the film, which remains in development, in light of the new agreement with Marvel."