Wired.com has a succinct article here which brings up some interesting points:
The quick story is that Google Chrome Helper isn’t really the problem.
It tends to go on the rampage when there’s a rogue extension or when
Google Chrome’s plug-in settings are configured to run everything by
default. ... but most users in the Help Center forums seem to run into trouble when it’s working with Flash content.
“Google Chrome Helper” is the generic name for embedded content that runs outside the browser. Browser plug-ins aren’t features that are rendered by HTML code; they involve content that needs to be pulled in from elsewhere. ...
The fix:
Disabling Helper’s auto-helping is easy, and it won’t prevent you from using plug-ins. You’ll just have to opt in to view plug-in content on a case-by-case basis. ... First, shut down all your Chrome windows without quitting the program. In the Chrome menu, go to “Preferences,” scroll all the way down in the menu, and click on “Show advanced settings…” The first item in the expanded advanced settings list will be “Privacy,” and click on the “Content Settings” button right under that. About halfway down the content settings list is a “Plug-ins” entry, which will likely be set to “Run automatically.” Instead, select “Click to play.”
I know this is a lot of copy 'n' paste, but it is some very interesting information.