Wording on Volrath's Shapeshifter
Sometimes Google does wonders. According to the January 2009 Update Bulletin, the oracle wording was changed because of the new layering system rules. 


  Oh, Volrath's Shapeshifter. Sometimes when the rules are systemically changed for the betterment of the game as a whole, and for most cards in general, one or two cards get thrown under the bus. That's what happened to Volrath's Shapeshifter. When the continuous effect layer system was implemented, different kinds of continuous effects were broken out so they'd apply in a set sequence. It was determined that copy effects would apply before control-change effects because all existing cards—except one—would work that way. (Switching those layers to save Volrath's Shapeshifter is not an option; if we did, Copy Enchantment copying Confiscate, or Clone copying Sower of Temptation, to name a couple of more modern examples, would cease to work as you'd expect.)
  
  The reason Volrath's Shapeshifter breaks under the layer system is that it cares about the top card of its controller's graveyard—so its copy effect is dependent on who controls it. Say Player A controls Volrath's Shapeshifter, then Player B Confiscates it. Volrath's Shapeshifter will continue to look at Player A's graveyard. That's because Volrath's Shapeshifter knows who its original controller was, and its copy effect is applied before Confiscate's control-change effect is applied to swing it over to Player B.
  
  To handle this, Volrath's Shapeshifter's effect was changed from a copy effect to a text-changing effect (which happens after control-change effects). Most text-changing effects change a single word of text, like Mind Bend does. Volrath's Shapeshifter changes all its text, and expands the definition of "text" to include color and mana cost, among other things. It's ugly, but it does the trick.
  
  I'd love to tell you that I have an elegant fix for this card, and that's why it's on the list. Nope. I'm deleting some unnecessary text from the card, putting in a comma, and fixing the italicization of its reminder text. (The unnecessary text is that Volrath's Shapeshifter's ability says that it works "as long as Volrath's Shapeshifter is in play," but that goes without saying, so this is just redundant.)


The short version is that with the copying effect version, if someone steals control of the Shapeshifter with Mind Control or something similar, then the Shapeshifter would have continued to look at the original controller's graveyard, not the new controller's graveyard, which is counter-intuitive. So the text-changing ability was given instead to make it work as expected.

I still have no answer to the second part of the question, though.