Perhaps the biggest threat to Google's increasing dominance of internet search and advertising is the rising fear, justified or not, that Google's broadening reach is giving it unchecked power.
This scrutiny goes deeper than the skeptical eye that lawmakers and the US Justice Department have given to Google's proposed ad partnership with Yahoo. Many objections to that deal are financial, and surround whether Google and Yahoo could unfairly drive up online ad prices.
A bigger long-term concern for Google could be criticisms over something less tangible - privacy. Increasingly, as Google burrows deeper into everyday computing, its product announcements are prompting questions about its ability to gather more potentially sensitive personal information from users.
Why does Google log the details of search queries for so long? What does it do with the information? Does it combine data from the search engine with information it collects through other avenues - such as its recently released web browser, Chrome?