Get Glyph of Indomintability over the brightbrew charm. I'd also make sure you have clutch of fortitude if you don't already so you can use it on really heavy hitters.
Spec is fine, though make sure you have a stack of glyphs of growl and mangle to swap out for the maul.
Rotation is okay. Most of the time I open with a berserk right off the bat or after I mangle and lacerate once. After that it really depends on the fight what rotation I use. I don't tend to favor lacerate stacks on bosses that it'll drop off on early (unless I want to do more damage when I'm "off", like on Marrowgar or Sindragosa). I also would prioritize getting that 5th stack of lacerate up earlier; you should be pulling with FF, then charge, mangle, laceratex3, mangle, laceratex2 and FF. That will give you a bit more overall threat if you can keep the stack up. If you're worried about burst, start with berserk.
In terms of gear, you might choose to lay off the T10 until you get to harder content. The 4p is great, but you may not really need it and it might serve you better to get 264 gear that's easily obtainable (like Cultist Spaulders). Otherwise prioritize getting the Toskk's and trying to find something of a replacement for that neck.
I'm more curious about the spec. Right now I do a fair amount of offtanking and switching to cat mid fight (Putricide, Festergut) so I got SA, but I've been really tempted to get KotJ for the enrage damage burst bonus. For those of you who have tried it, how do you like it? Is it noticeable at all?
I was going to check your tank gear out on WoWHeroes, but you seem to have two cat sets.
I'm in a similar position with the off tanking, when I first got the 4p tier10 bonus I tried out KotJ but as I need two specs (cat and bear) for raids I decided to drop it for a 'normal' spec. It's a nice idea, but unless you reallllllly wanted the extra damage I probably wouldn't bother. By looking at your current off tanking spec, for the fights you mentioned (Putricide and Festergut) I'd put points in improved mangle and grab the glpyh and use mangle spam for combo points, I'd drop the points in Shredding attacks.
As you're in cat gear I thought I'd try rate that a little, personal preference, but it might be worth dropping agility for hit rating on gloves as you could make full use of the hit. Try convince your guild to give you a Deathbringer's Will! (I'm not having any luck, but you might!).
My Armory; http://eu.wowarmory.com/character-sh...hor&cn=Vaneris
I have a couple of questions. Is it worth me dropping a few shifting gems in red slots rather than gemming full stam? In regards to gear choices, I've decided to take armor pieces at the expense of hit rating, is that worth doing or would the threat from hit be more valuable to me in your opinion? Should I carry two sets, one for hit and one for armor? Thanks in advance for your pointers!
While I could go for the hit on gloves, agility is worth more even below the cap. That it can double as a tanking piece without significant loss if it has agility on it made me decide to go for that enchant.
On Fester/PP, I'd never do manglespam with the glyph; I need to make sure taunts always hit. It's really not that critical. It's really not that big a deal, damage wise; it just helps that I don't have to change my rotation much.
No chance on me getting a DBW, as I only do a 25-man in a very small pinch right now.
And I don't have two cat sets; it's likely that it just saw me in my tanking spec and cat gear, which is what I do all the time. The reason I mention KotJ is that while it's not that special for doing extra damage (imp mangle is better) it's much better for getting initial burst threat, which is an issue some times.
As to your point - I don't think there's much value in going with shiftings ever. Darksend does. I think (especially with the icc buff) that stam is simply the way to go. Armor pieces are better than hit rating; only you can know whether threat is enough an issue for it to matter. The only time I care about hit is when I want enough to make sure taunts aren't resisted.