Google Docs is a free, standalone product, as well as a component in the broader collaboration and communication suite Google Apps, which comes in free and fee-based versions and is designed for workplace use.

Barkah, founder of BlueWax, an enterprise application consultancy based in Toronto, highlighted what he considered three flaws in the way files are shared in Docs, which lets people invite others to view and edit their word processing documents, spreadsheets and presentations.

First, Barkah noted that images inserted into a document are assigned their own URL, so that someone who has been given access to the document can continue to call up the image even if the document is deleted or if the document owner removes their access rights. "If you embed an image into a protected document, you'd expect the image to be protected too. The end result is a potential privacy leak," Barkah wrote.

Rochelle countered that images are kept independently of the documents in which they appear for fear that deleting them would break references to them in other documents and external blogs. "In addition, image URLs are known only to users who have at some point had access to the document the image is embedded in, and could therefore have saved the image anyway -- which is fully expected," Rochelle wrote.

Ultimately, document owners can request that images be purged from their account by sending an e-mail to Google's support team at docsimagedelete@google.com.