For your spec, I strongly recommend using this spec as a main tank: 5/58/8. Reckoning isn't good enough to dump 5 points into it.
Definatly get rid of reckoning.
1) it only proc's on clean hits (if you block, dodge, parry, or they miss, it can't proc). if you have holy shield up at all times like you should, your not going to get hardly any clean hits, which means that 10% proc chance is even worse now.
2) all it does is get you one extra auto attack. vengeance stacks outrageously fast and auto attacks even with broken promise (last laugh is faster/smaller white hits) are not remotely significant in a raid. it's like an extra 3-5k extra damage per proc. (and i would assume you would get a proc MAYBE every other pull)
it's a horrible talent for tanking.
As for me, i prefer getting the 5% crit from conviction rather than the 15% SoV damage from seals of the pure. Personal prefference; i love me some phat shield of the righteous-es
It leaves two points to throw where ever you like. I somtimes put them in Divine Guardian and sometimes improved HoJ. Only go 1/2 into improved judgements, 2/2 is a waste because you won't get any more judgements in when using a proper 969 rotation.
There are some "high threat" builds that drop some of the damage mitigation and suvival talents for more crit and damage in the ret tree. In my opinion, the extra threat generation of these builds is unnecessary, and not worth losing prot talents like Judgements of the Just and Ardent Defender.
You shouldn't need to tank with seal of wisdom up. Put blessing of sactuary on yourself, and pull more mobs if you're having mana issues. If you're having mana issues, you're not getting hit enough anyway, so your healer is bored, pull more mobs!
One last thing, never gem for parry. One point of parry is worth less that one point of dodge for avoidance %s. If you have to use a couple of purples to activate your meta or to put in a red socket to get a bonus, use a dodge+stam purple instead.
For Raid's you shouldn't need or be running Seal of Wisdom. The downside of SoW as the general case is 2 fold:
- Seal of vengence glyph gives pallies a get out of jail free card on expertise. Reducing parrys will help both threat and mitigation.
- Nerf's your threat a bit (SoW vs SoV/B threat). If you run with a highly geared group, you're going to have problems with things like maly or potentially patchwerk.
I like and use SoW a lot on heroics because for the most part, i'm just not getting hit enough for the heals to top me off (and thus the expertise loss actually helps SA), but you shouldn't be having that problem in raids.