Prot pallies and expertise.

[Omang]

I tried to give advice to a guildie of mine on what to go for on their prot pally, but according to the other tanks in my guild I was wrong.

Here's my amory, http://www.wowarmory.com/character-sheet.xml?r=Garrosh&cn=Omang. I'd appreciate any advice I could get if I'm doing something wrong and any links to guides I could read up on.

[Dasverlassen]

I'd throw +30stam gems in your boots and gloves, your expertise is very low, I'd recommend getting the helmet from Triumph emblems.
The Black Heart from reg ToC is probably better than your brewfest trinket.
Other than those changes I don't see anything wrong with your gear

[Grannus]

Expertise is our new #1 threat stat until 26 (6.5%)

Everything else looks fine (follow Dasverlassen on doing your boots and glove gemming), though maybe 240 Armor or 18 Stamina on your gloves rather than 2% threat 10 parry. Glyph of Indomitability would be better to use over your Brewfest trinket.