They seemed very clunky, and it made it seem like Flame Leviathan was going to be an epic amount of fail.....but it wasnt.
Flame Leviathan is one of the most fun encounters I have done so far in WoW. You get to drive around in big tanks or motorcycles, shoot gnomes onto the boss, and generally much around. It is an easy fight, but man blowing things up is fun.
You get to do metric tons of damage, even if you are a tank or a healer. The beauty of this fight is that you can try everything. It is easy to learn the vehicle controls and there are no too many options as to confuse you.
So, here is a cheers to blizzard on a fun encounter that you dont have to wipe on 20 times to figure it out. It is easy like Naxx, but a whole hell of a lot more enjoyable.