The second cool thing about Improved Fire Nova Totem is that it stuns all targets for 2 seconds. It stuns melee and caster alike, as well as stopping spellcasting even if the stun doesn't proc on Rank 1. (Drool. Me likely to stop spells!) The stun ability promises to help me a great deal in PvP, where I am famous for stinking up the joint.
It does hefty damage, too. Despite the tooltip saying that the nova inflicts only 841-941 fire damage, with spellpower adds on my gear and the correct supporting talents (like Call of Flame), I achieve the 1000+ damage burst in the top screenshot on a regular basis. By adding the Elemental Fury talent, I've seen the nova crit 2200+ at this level. That means that the Fire Nova Totem does as much damage as a Lightning Bolt spell. Now, granted, Lightning Bolt at Rank 12 only costs 236 mana to cast (vs. the totem's 806 mana), but even with Lightning Mastery, it still takes 1.93 seconds to cast Lightning Bolt and 1.45 seconds to cast Chain Lightning (which costs 725 mana) whereas dropping the nova totem is instant and it procs in 1 second.
So how does it work in practice? Dude, I drop this little guy into all my fights where I'm able to -- almost as often as it cools down. You don't really worry about mana much anyway when you spec Elemental and use the Water Shield, so the cost of the mana versus the damage it causes -- to all targets -- with more speed than other spells makes it well worth the mana cost. I can't even remember if I have drinks in my bags, so it's certainly not slowing me down with mana, especially if you spec Unrelenting Storm.
The only thing you need to worry about with the Fire Nova Totem is aggro. Don't throw it during PvE where you can pull more mobs than you can handle and don't throw it in groups unless you've got good threat management. But I tell ya, the Elemental tree is pretty beefy. I don't worry too much about adds because I can almost always take them down. Worst case, I use Thunderstorm and run away. (But I've only had to do it once!) I'm having so much fun with my Elemental Shammy that the Death Knight I rolled doesn't seem as OP as I originally thought it was. I can't wait till this talent tree goes live!
Want to know more about all the new spells and talents in Wrath? Our Skill Mastery series has more lowdowns on the new skills you'll be able to use in Northrend. And if going Shaman is more your style, the WoW Insider Directory's Shaman page has everything you'd ever want to know -- and then some.