This is the 35th tool that I have used to re-create my electronic portfolio. The process moved very smoothly; I was able to convert all URLs to weblinks. The tool allowed me to reconstruct my portfolio in less than an hour, copying the information from my PBWiki portfolio where I had the URLs on the page (and the links). I easily uploaded my graphics. All of my other artifacts are web links. In Google Sites, there is 10 GB of storage space per account for all files for every Google Apps domain. (In the Premiere and Education versions, there is also an additional 500 MB per user in the domain).
 
I prefer to have the links open a new window (and the portfolio remains open), which was option when you create a link.  When an artifact is opened, the reader can then close the window to go back to the portfolio.

To aggregate assessment data, a spreadsheet could be created to collect quantitative data. There is great interactivity to this program, because it is a wiki. Therefore, this tool would work very well for an interactive presentation portfolio but other tools will need to be used for summative assessment.
 
The real advantage of GoogleSites is the many different tools, gadgets and widgets available, as well as the file management system. I was able to upload files as attachments. I created a Table of Contents on the upper left side of the page (the Navigation, with links to each section on the site, which automatically shows on each page. I was able to create each page as I created the first link. I am impressed with this tool. I was able to create this hyperlinked set of web pages, with no knowledge of HTML.

I still do not know if files uploaded to a File Cabinet page can be accessed by a hyperlink from a regular web page. I also do not know if files added as an attachment at the bottom of a page can be somehow inventoried (a list of links to all attachments in a site). UPDATE: This feature is now available as of August 2009. Google announced a new attachment section was added to the Google Sites management section for easier management of all uploaded attachments to Google Sites. Now you can see all attachments and which page they appear! Very useful for an ePortfolio. I wonder if you can generate a link to an attachment from another page?

This program would work well for a presentation portfolio, but GoogleSites would work better if the goal is a learning portfolio, with interactivity and feedback. Each page can have comments added, which is the nature of any wiki. Others can also be invited as a contributor on a page, by inviting collaborators. Sites can be restricted to only people you specify, or everyone in your domain. The Collaboration feature functions in a very similar way to GoogleDocs. Comments can be added at the bottom of any page.