I've published 26 of those overview videos so far, with the videos also proliferating into the BGG database, and we have ten more still in the can — all from day one! You can see them all in our Gen Con 2018 playlist, which will likely grow to two hundred-ish videos by the time everything has been posted.
Thanks to the increasing overlap of games being released at both Gen Con and SPIEL — as well as games being previewed at Gen Con ahead of SPIEL — these videos also serve as previews on the SPIEL '18 Preview. If you see a game cover on this preview with the "play" icon on it (as shown at upper right), you can click on the cover to launch the video within the preview. In addition to our Gen Con coverage, these videos come from Spielwarenmesse, Festival International des Jeux, GAMA, Tokyo Game Market, and Origins Game Fair, not to mention the occasional appearance by Rodney Smith of "Watch It Played", BGG's "Game Night!" crew, and one tall-ish news guy.
Many more video overviews to come in the weeks ahead, both from Gen Con 2018 and from sample games that publishers have sent me ahead of SPIEL '18. Only nine weeks remain for preparation for that show. Deep breaths...