Even if you can't combine spells, magicka students will have no shortage of options, with over 85 spells divided into five schools of magic – destruction, restoration, illusion, alteration, and conjuration. Longtime Elder Scrolls fans may notice that the school of mysticism is absent. That's an intentional move on Bethesda's part. “It always felt like the magical school of mysticism – isn't that redundant?” Howard says. The spells formerly housed under the domain of mysticism have been moved to other schools of magic.
But this quote indicates there are 6 skills:
Three prominent nebulae dominate the Skyrim heavens – the thief, the warrior, and the mage. Each of these represents one of the three master skill sets. Each nebula houses six constellations, each of which represents a skill.
And then this image shows 7 of something:
http://www.gameinformer.com/cfs-filesystemfile.ashx/__key/CommunityServer-Components-ImageFileViewer/CommunityServer-Components-SiteFiles-imagefeed-featured-bethesda-elderscrolls-elderscrollsv/SkillsMenu.jpg_2D00_610x0.jpg
Are these skills or schools or something else?