Currently, no one plays a Shapeshifter -- at least, not anyone who has been even remotely active in the past three years. Most people think that the class is simply just too weak when stacked against the other mage classes, which I suppose could be considered true. However, there is one other flaw with Shapeshifters that I see.
You can't actually shapeshift.
The Shapeshifter class has three 'shifting' spells that can cast that give some kind of bonus to the caster -- shift bear, shift giant, and shift owl. Yet, when you cast the spell, aside from the spell message itself, there is nothing that indicates that the Shapeshifter actually 'shapeshifted.' You can't look at the person and see which shift they might be using.
Therefore (and I know that this just adds more into the possible coding playthings, you coders can maim me later), I think it might be interesting if the Shapeshifters gained some kind of ability to morph into their chosen totem animal. Possibly without the major bonuses/negatives that racial morphers get, as you wouldn't want to take away from their uniqueness at all, but at the very least a cosmetic enhancement to give the Shapeshifter class some roleplay credibility, if they have no hope of matching up against their other mage brethren in terms of power.
Yes, I suppose that you can just roleplay out whatever shifts you may have made as a Shapeshifter, but I think it might be nice if this were taken one step further and enhanced by actual game coding, so as to give the class some attractiveness as a choice for up-and-coming Magi.