According to the memo (which you can read in its entirety after the jump), the move will allow Ziff Davis to "Simplify and Focus," letting the publisher direct their attention to multi-screen flagship publications IGN and AskMen.
This year would be 1Up's tenth online after launching in 2003 in support of Electronic Gaming Monthly. Ziff Davis sold 1Up to Ugo back in 2009 before purchasing 1Up and Ugo together under a buyout of IGN Entertainment earlier this month.
From: Vivek Shah
Date: February 21, 2013
Subject: Staff Announcement
Today, we took some difficult but important actions that will ensure the continued growth and health of IGN and AskMen. Before I go into more details about the changes, you should know that they resulted in the elimination of jobs at IGN.