1) any parry gems should be switched to dodge gems. Parry hits it's diminishing returns mark faster then dodge, and dodge also converts to avoidance at a lower value (1 point of dodge > 1 point of parry).
2) You have a +hit of 3% - if you ever find yourself agro starved, look into gemming for +hit
3) Look into getting a Indestructible Plate Girdle made for yourself - it would be 26 iLevels higher then what you have now and is a good investment (your running Ulduar 10/25, so Rune Orbs should be dropping regularly for your guild)
Drop the points in Epidemic and put them into 2H Weapon Specilization
Take out Ubreakable armor and get Howling Blast - the damage reduction isn't all that great and the DPS given by HB should be roughly the same as an Obliterate most of the time (hence why I got you to drop Epidemic - with HB being used every time it's up, you'll keep your Frost Fever up 100% of the time)
Replace Glyph of Frost Strike with the Obliterate one - most of your RP should be going into Rune Strikes, and less so Frost Strikes and you should be using Obliterate every time it's available.