You could access your DotNest sites securely through HTTPS from day 1; however, this required you to use a custom port. E.g. when accessing your site "mysite.dotnest.com" securely you would have used the URL "https://mysite.dotnest.com:8443" with that ugly "8443" at the end. But not any more!
All DotNest sites can now be accessed securely without using a custom port, as it would be natural, e.g. like "https://mysite.dotnest.com". Much more convenient, as this doesn't require you to do anything special.
Don't be afraid if you have links pointing to the old URLs: those will get automatically redirected to the new ones!