Linux users have been waiting quite some time for Fedora 18. The final release has been postponed seven times, for a total of more than two months, from the originally planned release date of 6 November 2012 to the actual release on 15 January 2013.
No one can accuse the Fedora developers of being slaves to a calendar, or succumbing to pressure to ship a release before they believe it is really ready.
According to their public statements, the primary causes of the multiple delays were a rewrite of the anaconda installer and a new utility called fedup, which is a new Fedora upgrade utility.
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Also: What's new in Fedora 18