Rulings

• 2004-12-01
  If an Equipment becomes a creature, it can no longer equip a creature. If it's currently attached to a creature, it becomes unattached (but remains on the battlefield). You can activate the Equipment's equip ability, but it won't do anything.
• 2004-12-01
  Each artifact land has a converted mana cost of 0. March of the Machines makes them 0/0 creatures, which are put into the graveyard as a state-based action.
• 2007-07-15
  If a noncreature artifact becomes an artifact creature this way and then another effect animates it, the new effect overrides March of the Machines's effect. For example, Chimeric Staff is a 4/4 creature while March of the Machines is on the battlefield. If you activate Chimeric Staff's ability and choose X = 5, Chimeric Staff will be a 5/5 artifact creature for the rest of the turn.
• 2009-10-01
  A noncreature permanent that turns into a creature is subject to the "summoning sickness" rule: It can only attack, and its abilities can only be activated, if its controller has continuously controlled that permanent since the beginning of his or her most recent turn.
• 2004-12-01
  If a noncreature artifact is also another card type, such as enchantment or land, it will retain those types in addition to being an artifact creature.