Wow RedBeard, that would be awesome. Now I wonder if there is a way I could keep track of the internal cooldown it has..
I guess I could modify that mod to start a timer whenever it notices eclipse proc through the combat log or whatever it uses to notice party procs. Then I could toss up a timer bar on my mains screen to watch when the ICD is about to finish.
That would really help boost the moonkin dps. (its worth over 500dps to use eclipse properly according to EJ)

Doing some more searching I stumbled upon this: http://raidcomp.mmo-champion.com/
Its a lovely little tool that lets you play around with buffs.

It really looks like Earth and Moon and CoE are both worthless as far as debuffs go due to Ebon Plaguebringer being so easily spread. I think I will keep the talent points in it though for the 3% self damage increase.
CoE is definatly out though.

As for why a DK over a paladin. I maintanked on a paladin soloboxing for quite some time, and started getting rather bored with it in the end. Its just too easy. A DK (from what I've read) does more damage, it also looks more fun. I will be leveling the group to 60 using a paladin, so if worse comes to worse, I'll just pop up him to 80. My wife also plays a paladin as her main, so if there is a heroic that I just can't figure out with a DK tank, I could let her tank it and just 4box.

I think the shadow priest would be too complicated for not enough payoff. The farthest I ever went with spriest was SSC, and it was pretty intense to play the class to its max. A lot of cooldown watching.
It does bring a nice health/spirit buff, but I would lose out on armor/stats from MotW. I wouldn't have to cast CoE due to Ebon Plaguebringer, so it wouldn't affect the lock. Replinishment will exist from the mage by the time I even create the characters.
I did take a good long look at the spriest based upon your comment, so thanks for that. However I don't think it fits as well as the boomkin, and it would mess up my 5man boomkin team :) (using RAF grants to pop 4xboomkins to lvl 60)