Google's new Google Web Accelerator can't dodge the pro forma privacy concerns raised with anything new that the search giant does. PaidContent points to raised eyebrows (other examples here and here).
The software tool that mildly speeds up perceived download times for the web winds up collecting the same sorts of traffic information that ISPs have had for decades (and Google has had ever since it bought web log analysis firm Urchin).
But, being Google - presumed to have the competence to do something with it - some people seem concerned.