Bidding on Trademarks
While it's obviously a move to protect themselves from litigation, it's a delayed move, but still a smart one. Most other pay-per-click providers have established guidelines on trademark bidding and have actively limited the practice for some time. Google however, still allows trademark bidding.
The development will not directly affect any advertiser unless they are directly bidding on a search term that is trademarked. Most providers of pay per click solutions allow bidding on trademark terms if there is an obvious distribution (affiliate/partner) arrangement. Meaning that SportsMart can bid on the term Nike, but Adidas cannot.