They can be really useful to new users with no or little experience. From what I've seen, when people use the web for the first times, they "don't know where t

They can be really useful to new users with no or little experience. From what I've seen, when people use the web for the first times, they "don't know where to go". They don't have surfing habits yet and they're completely overwhelmed by so much to choose from. If you offer people a handful of useful/informative/fun sites, it'll be much easier for them to pick something and get going. If this is implemented carefully (and I think Mozilla is putting a lot of though into it) this could really be a win-win-win situation for Mozilla, the users and the advertisers. Also note that chances are that you never see those ads because Firefox will continue showing you the sites you visit often.