It is quite different to a lot of coverage - the focus being how GW2 and TOR "auto-compete" - but then Kill Ten Rats isn't simply about reporting MMO news. :D
Take a look at the Guild Wars 2 elementalist profession with it’s four “stances.” Each stance puts the elementalist into a different elemental attunement. Fire attunement allows the elementalist to start doing massive AoE damage. Air attunement switches the elementalist’s DPS from AoE to single-target. Water does support and healing, and Earth puts the elementalist in to a tank mode. That way the elementalist can watch the battlefield to synergize with the multiplayer mass to provide for whatever role is necessary at that time. The elementalist is watching to help the event or party instead of grouping to negate the elementalist’s dependencies.
It’s a very slight difference when looking at a role built on negatively reinforced dependencies versus a role built on positively reinforced synergies. It gets even worse because it is rarely so black and white anyway. Most MMOs take a mixture of both into creating classes and group content. Yet, it’s the focus that really matters, and Guild Wars 2 and SWTOR seem to really have a different focus in this regard. The battle of these two giants is truly old versus new in the sense of role definition. Personally I’d rather be looking for players rather than roles. Caveat lector.