My toon, Neom on Runetotem (US),I'm not sure what to spec due to the changes that have occured recently with hit rating and spirit. Can anyone give me a little insight on how to spec or correct gem's on my toon to maximize my dps for PvE?
Unless I am mistaken which I could be, but I think anything over 340 hit for a TTW / Fire mage is a waste. 340 is +13%, +1% from Dranie, +3% from Moonkin / Priest = 17% cap. So that is your first thing to fix, most likely get a better trinket.
First, replace you Meta gem please.  Get the Chaotic one.  Next, if you run with a Shadow Priest or Moonkin, you only need 369 hit rating, for horde, not sure the exact # for Alli since you will get another 1%.  So you can afford to lose a couple of hit gems and replace them with Spell Power gems.  Next, you'll want the Glyph of Fireball, not FFB with that spec.  As far as the spec goes, you want to put 5/5 into Imp. Fireball, and I have never worried about Imp. Fire Blast or Inceneration.  Here's what my spec looks like: http://www.wowhead.com/?talent#of0Vcu0cZ0Ec0RhIhVubhct
I choose to go 3/3 in SotM, but alot of people like Flame Throwing for the extra range on your LB and Scorch (if you have to use that).  That should help some.  Good luck!
That is the exact spec I am running, but I find that with LB crits, and everything else combustion in its current state is almost useless. I think I might drop it and figure out a way to get 2/2 flame throwing for range. On some fights its very handy.
341 for alliance to hit cap if you have a boomkin or spriest and a draenei in party (not raid-wide). Definitely ditch the meta you're using. Swap to the sp/spirit leg enchant, it's not fantastic but with the MA change it's more an active benefit than stam. Your spec: put 5/5 in imp fireball (first tier), it's your main nuke (or should be) and you use it far more than fireblast or scorch, reduce it's cast time as much as you can. The other two points are better to be placed in either flame throwing (more useful if you still have to cast scorch) or filling out Student of the mind, or arcane meditation if you're having mana issues.