MeeGo is a Linux-based open source mobile operating system project. Primarily targeted at mobile devices and information appliances in the consumer electronics market, MeeGo is designed to act as an operating system for hardware platforms such as netbooks, entry-level desktops, nettops, tablet computers, mobile computing and communications devices, in-vehicle infotainment devices, SmartTV / ConnectedTV, IPTV-boxes, smart phones, and other embedded systems. MeeGo is today hosted by the Linux Foundation.
[UPDATE] Nokia decided to switch to Windows Phone as their primary mobile platform, thus abandoning Meego as a mobile operating system. It is not known at this point if a Meego tablet will be released by Nokia.