The Google Network has some cool features that should concern its competition. For starters, it can disclose the sites you run ads on and report performance on a site-by-site basis. This enables you to focus buys on those sites (inventory allowing). An inability to see where your ads appear has always been a barrier for some advertisers.
Cons
One drawback is there are no inventory level guarantees. This is true of any network, but with Google it can get even more difficult as you can't reserve inventory (expensive home page buyouts aside). A bidder can bump you out of certain placements by bidding higher and raising his maximum CPM.