Can't watch the videos right now so I can't comment on them, but I'm sure I'll be seeing lots of ads for the game all over my TV watching soon enough knowing Microsoft.
As for the GT5P vs. Forza 2 sales arguments, I'm sure bundles helped both games reach higher sales, but one thing that hasn't been brought up is price. GT5P released for $39.99 where Forza 2 was a full price game at $59.99. Obviously both games were/are cheaper to find later in their life spans now, but I think it's an important factor to consider since a $40 price point will lead to more sales for those on the fence a bit--especially those who knew it was a demo. Also, I don't think there were much for bundles in North America (I can't recall any in my area of Canada) for GT5P and I think it shows with the really lackluster *disc* sales stats.
As a side note related to people knowing/not knowing it's a demo, I still see flyers now and then that just show it as "Gran Turismo 5" in the advertising which always gives me a chuckle.
Consoles Owned: Atari 2600, NES, Sega Genesis, Sega Saturn, N64, Gamecube, Wii, XBOX360
