This question was posed to me in the comments section of my last article:
"What other neat/essential tanking talents are you giving up in order to but at least 36 talent points into blood?"
The short answer; Almost nothing.
The truth of the matter is that every essential tanking talent, aside from your cooldowns, come in the first tier of every tree. With just 5 points invested into each tree you come away with 10% to parry while your blood runes are on cooldown, 15% more armor from items, and 5% to dodge. After those first 15 points each tree has its own 1 minute cooldown tanking ability. Blood has Vampiric Blood (which I discussed in my last article). Frost has Unbreakable Armor, Unholy has Bone Shield. As of right now, Unbreakable armor gives you 25% more armor, 10% more strength, and 5% more parry all for 20 seconds of every minute. Bone Shield gives you 5 (when glyiphed) bones that swirl around you offering 40% damage reduction as long as a bone is still active, and each hit makes you lose a bone. Bonesheild lasts a minimum of 12 seconds and can last a pretty good chunk of time depending on how many attacks you can dodge and parry. All of these seem pretty equal right now, maybe even vamp blood is on the low end of usefulness.
That should all change with 3.0.8.
I also have some nice links for all you aspiring Death Knights.
Elitist Jerks Forums - Death Knights class mechanics forum. Home of great theorycrafters and math geeks that do the dirty work to tell us what works best.
Over at Lichborne (wow insiders DK blog) they have a great article about the different reputations of WotLK and what you will want to grind to gear up your Death Knight. As well as another supremly helpful guide for basic defense gearing of your DK.
For you PvP Death Knights (and any pvp nut in general) we have Arena Junkies. As with all arena junkies forums the DK forum has a lot of crap to wade through, but you can really find some gems of great pvpers sounding off on their thoughts about DK pvp.
I think it would be negligent of me to post links without including the only other wow blog aside from WTFspaghetti that I read daily. World of Ming is what you would get if you took the wow general forums and combined them with TMZ and the Jerry Springer show. Non-stop E-drama concerning "wow arena celebritys" mixed with QQ and even some occasional quality insight into wow pvp. Best (or maybe just most) trolls on the web. Even if the article sucks the sideshow that is the comments section is always worth a chuckle. All run by the "Rogue Hero" Ming. With a lisp, heavy asian accent, and an imaginary wife the comedy practily writes itself.
Thats it for now, I am level 78 pushing to 80. Gotta get started on the gear grind...