These aren't ads though, and Canonical isn't collecting this data with the intention of serving you ads -- they're just diplaying relevant Amazon results along with normal web results when you do a web search through the dash. It's also very easily disabled, and you still have the option of doing local searches confined to your machine.
Ok so when I'm searching for something on my computer I'm presented something other than the files I'm searching for right?
From Wikipedia:
"Advertising is a form of communication for marketing and used to encourage or persuade an audience (viewers, readers or listeners; sometimes a specific group) to continue or take some new action. Most commonly, the desired result is to drive consumer behavior with respect to a commercial offering, although political and ideological advertising is also common."
Sounds to me it's exactly the definition of advertising.
