Nearly 25% of cell phone users in the US say they’ve seen an advertisement on their phones in the past 30 days, according to Nielsen Mobile. In Q4 2007, there was a big jump in the number or people reporting that they had spotted advertisements on their mobile phones. This figure rose 38% to 58 mln users who said they saw advertising on their cell phone, compared with only 42 mln who said they saw advertising on their phones in Q2 2007.