sounds like you're excited because it's something new. Tanking is super fun at low levels, I mean you're a god essentially almost nothing can really hurt you, at least not on it's own. Tanking can be fun at high levels but in raids you don't just pull every single thing, some boss fight may consist of you just sitting there (not often though), which can lead to tanking being rather boring.
There is a certain set of how fights will go, and although some fights in a raid may have all new mechanics, in the end most of them are the same with just another way of doing the mechanics. Being a DPS of course you'd be watching your big numbers fly and meters, as a tank you're swapping taunts off the other tank