Hit has always been different in pve and pvp.
From wowwiki on spell hit: (
Spell hit - WoWWiki - Your guide to the World of Warcraft)
With Talents and gear combined, chance to hit with spells can reach 100%. Casters should keep this cap in mind when considering their gear. For PvE raiding, bosses are considered to be 3 levels higher than the caster, meaning that +17% is the most that will be effective. For PvP, anything more than +4% chance to hit is typically excessive. Note that some classes (for example Paladins and Rogues) can spec to gain extra chance to have spells miss them. Also, some abilities (e.g. - Cloak of Shadows, and spell resistance for binary spells) give the player using the ability extra chance to have spells miss as well. Extra spell hit does in fact mitigate this extra chance to miss, but is otherwise useless.
wowwiki on hit: (
Hit - WoWWiki - Your guide to the World of Warcraft)
The base chance to miss with maximum weapon skill against an opponent of equal level is 5% for two handed and 24% for dual wield.
...As shown above, your base chance to miss a raid boss while dual wielding is 27% with auto-attack on both hands. Your base chance to miss a special attack is 9%...
On the other hand, it is also common to see people over-value the benefit of hit rating. Some players stack hit rating indiscriminately without realizing that their hit is over-capped by a large amount. This is especially easy for classes that have lower hit cap, such as hunters. Any hit rating above the hit cap is useless. Therefore, one should adjust the hit rating so that it is not overshot by too much <--- Hunter hit cap is mad low, I've tried to say this before, seeing that I raided a ton on my hunter...
For example, imagine there are two helms with similar stats except that one has 20 more hit rating, while the other has 40 more critical strike rating (or other stats for classes that value crit less). Although 1 hit rating is better than 1 critical strike rating usually, 40 critical strike rating is better than 20 hit rating. Therefore, one should still choose the second helm even this means he/she will be further away from being hit-capped. In general, we should choose the piece of gear that provides higher improvement in damage output, regardless of whether it has hit rating or not.