Caps, Stats, and Good Info
Stat caps per level (Str, Dex, etc...): 
A) 1.5x your level from items (weapons, armor, jewelry, etc...) 
B) 1x your level from single-stat buffs (aka baseline buffs, like +Str or +Dex from a Healer or Shaman) 
C) 1.5x your level from double-stat buffs (aka spec line buffs, like +Str/Con or +Dex/Qui from a Shaman) 
D) Unknown as of yet if there is any caps from Realm Skill stats. 

- A, B, C and D all stack together. 
- By level 50, A+B+C is capped to a maximum of 350...And D goes on top of that 

Bonus hitpoints are capped at 4 * your_level. 

Each class gets a different amount of hitpoints for additional constitution. Warriors and Berserkers get 4.25 hitpoints for each additional point of constitution. 

Capped hp = Base HP+ : 

200hp from +hp items 
75 Con from Items 
50 Con from Baseline Buffs 
75 Con from Spec line dual buffs 

+con at startup stat allocation 
+con from levelup aquired con. 
 
 

Resistance caps:
- items give a maximum of +26% on any resists at lvl 50 (1 + (your level/2)) 
- race gives: 
Kobolds: 5% crush, 5% energy 
Norsemen: 3% slash, 2% crush, 5% cold 
Trolls: 3% slash, 2% thrust, 5% matter 
Dorfs: 2% slash, 3% thrust, 5% body
- buffs has no known cap. 
- realm abilities has no known cap. 
+Spec caps: 
A) +11 from items at lvl 50 (1+lvl/5) (weapons, armor, jewelry, etc...) 
B) +10 from Realm Rank 

- For a maximum of +21 to a spec (like weapon or shield) 
 
 

Benefits of Stats: 
50-200= 1% gain, per 2 points 
200-300= 1% gain, per 4 points 
300-350= 1% gain, per 5 points 

Still not known the actual benefits of Realm Skill +stat gains. 
 

Things that affect your chance to-hit something: 
- Enchanted bonus on your weapon (and bonus also increases damage contrary to what is said from Sanya) 
- Your level vs. their level (the higher their are than you, the harder they'll be to hit) 
- The number of people fighting the same opponent - this isn't group dependant. 
- Weapons Styles with bonus to-hit 
- Str, Dex, Qui...NONE of the base stats have any effect on your chance to-hit (I disagree with the Dex portion of this statement from my own experience) 

Things that affect your chance to NOT get hit by something: 
- Enchanted bonus on your armor 
- Weapon styles with bonus to defense 
- Dex affects your chances to Block & Parry 
- Dex & Qui affects your chances to Evade 
- Your level vs. their level (the lower the level they are to you, the harder it is for them to hit you) 
- Armor Factor on your Armor affects the chance to negate a blow (seen as a miss) 
- Absorb % on your armor affects how much dmg taken when you do get hit 
- AF also decreases the damage taken 
 
 

Effectiveness of Shields and Shield Spec: 
A) Shield spec has a base 5% chance to block +0.5% per spec point 
B) Enchanted bonus on Shields also affects chance to block (Unsure in what way, maybe A+B, or A+(AxB)) 

Small shields: (supposedly) has the base chance to block 
Medium shields: (supposedly) has an extra 5% chance to block vs. Small 
Large shields: (supposedly) has an extra 5% chance to block vs. medium and 10% vs. small 

Shield Sizes: 
Round = Small 
Kite/Heater = Medium 
Tower = Large 
 

Effectiveness of Weapon spec: 
1 to 2/3rds of level = 25-100% dmg 
2/3rds to 100% of level = 75-125% dmg 
100%+ = 100-150% dmg 

That scale is linear. 

Your damage continues to grow if your weapons spec is above your level, but slower. 
I believe each weapon spec point above your level adds about 0.66% to your damage. 
 

How stats affect weapons: 
Axes = 100% Str 
Swords = 100% Str 
Hammers = 100% Str 
Spears = 50/50 Str/Dex 
Staffs = 100% Dex 
 
Damage Calculation: 
 
Damage = WeapDmg (which is a possibly capped weapon DPS) * Delay * Quality * Condition * (WeapSkill / Target's AF) 

Also, there is an interesting formula for the effective AF of a piece of armor: 

Effective AF = Listed AF * Quality * (1 + (absorb * quality)) 

Notice the quality double-dipping which makes it extra important for armor. 
 

Weapons/Magic vs. Armor (From Classes of Camelot website): 
 
_______________Crush__Slash__Thrust__Fire__Cold____Earth__Electric 
Cloth__________-______-______-______-_____-______-______- 
Leather________-______+15%__-15%__+15%__-10%__-5%___- 
Studded/Reinf__+10%___-______-10%__-10%__+5%___+5%___+5% 
Chain__________-______-15%__+15%__-10%__-______-______+10% 
Plate/Scale____+10%___-5%___-5%___-10%__+10%__-10%___+10% 
 
this armor table is outdated - but will do for now