With our new O365 E3 site, we're pleased with the capabilities.
When running from our desktops we prefer to have a mapped drive letter to sharepoint and also to SkyDrive Pro.
We've followed the setup articles and logged in to the site with "Keep me logged in". Made the site trusted and added the sites and lync, microsftonline, sharepoint & outlook.com etc. to trusted sites and local sites.
When I open a site in O365 sharepoint and go to library and choose Open with explorer I can browse the site and use my drive mapping.
If I close the site or login to the site but do not go to libary and/or open with explorer I cannot use my mapped drive letters.
Am I missing something or is this the only way i can make that work.