Err hit rating? Yes, you should have that. There is some debate, currently, because the raiding hit cap of 17% is quite high, however. Basically, having 17% hit guarantees that you will hit the mobs every time. However, at the current level of gear, you are sacrificing a lot of crit/haste/whatever to get that hit rating. I think the SPriest writer did a breakdown of this, but basically the difference between getting the hit cap and not getting the hit cap isn't that big, because if you HAVE things like more crit, it means the spells that ARE hitting are hitting harder than the spells that hit all the time in the 17% hit rating scenario.

If you aren't really doing raids (except the Baradin Hold boss, say), you only need 6% hit rating (I think) to be hitting mobs all the time in heroics. After that, you can reforge away all the hit into other, more valuable stats. If you ARE running raids with a raiding guild, however, it might be worth it to hit that 17% cap. As Fox the SPriest columnist said, there are many utility attacks that you would not want to be missing like counterspell, spellsteal, whatever. Also, if it's right before a phase where you can't attack as much, missing your DoTs right before could mean a substantial DPS loss. You could also have bad RNG during a burn phase, or something, and miss a string of spells and waste most of a BL/TW/AH cooldown, or something.

TL;DR - if you're not raiding much, get to 6% and then get other things. If you are raiding, 17% hit is probably more valuable, atm.

Side note - Fox found that at about 13% hit you're doing more DPS than you would be at 17% hit on a raid boss, simply due to the extra oomph from things like crit and haste. But again, there are certain, important spells that you just don't want to be missing.

I'm afraid you mixed up his articles.

Hit rating is the most important stat once you hit level 85. As you level, you want to just have as much INT as possible.

The article you are referring to talks about "stat weights" which is something that you look at once you are ready to start raiding at the level cap. It's not something you worry about as you are leveling. Mage 101 is not the same as "leveling guide for mages."

Before raiding, there are 2 steps:

1. Still leveling - at this point, you do not care about hit.
2. At level cap, but under geared - You want to aim for about 8% hit rating for heroics.

As arcane, you want Int always, and crit is your main secondary stat now. As you are leveling, I would say your hit be at most 10% - anything more and you are weakening yourself. (Haste is still good, btw, just not as good as crit right now.)