I found a couple more of the more popular portal web sites (CMS), and I found using Google Trends that DotNetNuke is still at the bottom of the "trends" shown on Google. Hmmm... I then took DotNetNuke out of the trend and here are the results.
Google Trend Results for Popular Portals World-Wide
If this is data that we can rely on, then this shows some interesting "trends". :)
What will continue to baffle me for some time is the fact that so many people are intent on spending money on a CMS like Websphere or SharePoint when there are low or no cost solutions out there that are just as good or better (with a few exceptions, such as MS Office integration).