1. yes, the ones with the different color borders in Series 8 are a complete repeat of the base set of 55 cards.
2. the newest cards (series 7 and series
have a complete database listing in the Master List section of this site
3. wacky base updates? we'll have to wait for Brad (Bum Chex) to answer that
4. the ads are all based off of cards from All New Series 7. (and the ones on the backs of series 7 came from series 6, on series 6 from series 5, etc.)