What exactly do you mean by “front page”? What’s visible on your screenshot is simply the Google results page. I don’t know what search terms you used, but when I search for Pencil2D, it does show the latest version:
Are you sure clicking on the 0.6.6 link takes you directly to the download page, or does it take you to the 0.6.6 release announcement and you navigated to the download page from there? In the latter case it is expected that that page shows 0.7.0 rather than 0.6.6 because we do not maintain dedicated download pages for older versions on our website.
The reason I raised this issue is that I can see that it’s not the Pencil2D groups problem, but others may not understand this and think it the Pencil2D groups fault!
If the user clicks on the 0.6.6 link on the page, the correct page to download the latest version 0.7.0 loads.
I’ve done some other searches via Google recently and been supplied with totally incorrect information!