There's a good article about eight of the risks impacting Google, according to Google:

Here's a summary

1) Difficulty Scaling and Adapting Our Existing Architecture to Accommodate Increased Traffic and Technology Advances or Changing Business Requirements

2) Reliance on Bandwidth Providers, Data Centers or Other Third Parties for Key Aspects of the Process of Providing Products and Services.

3) New Technologies Could Block Our Ads, Which Would Harm Our Business

4) Proprietary Document Formats May Limit the Effectiveness of Our Search Technology

5) Index Spammers Could Harm the Integrity of Our Web Search Results, Which Could Damage Our Reputation and Cause Our Users to be Dissatisfied with Our Products and Services

6) Privacy Concerns Relating to Our Technology Could Damage Our Reputation and Deter Current and potential Users from Using Our Products and Services

7) More Individuals Are Using Non-PC Devices to Access the Internet, and Versions of Our Web Search Technology Developed for These Devices May Not be Widely Adopted by Users of These Devices

8) If We Fail to Detect Click Fraud or Other Invalid Clicks, We Could Face Potential Litigation as Well as Lose the Confidence of our Advertisers, Which Would Cause our Business to Suffer

There are areas that would definitely affect Google and its investors if not addressed properly.

[ Continue reading at Zdnet ]