Beware, wall of text pointing out flaws and issues with the Feline Way maneuvers.
Note that these are just the issues that I see that I think need to be fixed. In general, the Feline Way (or what's been written so far) looks pretty good to me.
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Attach
The Feline Way (Counter)
Level: Swordsage 6, Warblade 6
Prerequisite: 2 Feline Way Maneuvers
Initiation Action: 1 Immediate Action
Range: Personal
Target: You
When you initiate this Maneuver you can attempt to Grapple an opponent who attacks you in melee. Make an Opposed Tumble Check vs your opponents Attack roll. If you succeed his attack fails and you are considered to be grappling him. If he is more than one Size Class bigger than you you lose your Dexterity Bonus to AC and may be attacked via a one handed weapon. Your opponent must Pin you in a Grapple to remove you, and you get a Bonus to Grapple Checks equal to your Initiator level divided by 5.
Grapples usually require the participants to be moved into the same square(s). This maneuver does not require it or cause it. It should probably be changed to have you move into your opponents space, as normal for starting a grapple and fitting with the flavor.
You always lose your Dexterity bonus to AC when in a grapple. Did you mean to say that if you grapple someone larger than you, you retain your Dex bonus instead?
Also, how long does the bonus to grapple checks last? There is no listed duration.
Bitin' the Berries
The Feline Way (Strike)
Level: Swordsage 6, Warblade 6
Prerequisite: 2 Feline Way Maneuvers
Initiation Action: 1 Standard Action
Range: Melee Attack
Target: One creature
Duration: 1 Minute
Saving Throw: Fortitude Partial
As part of this Maneuver you enter the space of an opponent at least 1 Size Class larger than yourself, and do not suffer an Attack of Opportunity for doing so. If your attack is successful your opponent falls prone and is helpless for 1 round, and takes a -4 Penalty on all rolls for 1 minute if he fails a Fortitude Save (DC is 16 plus Strength or Dexterity modifier whichever is higher). If the Save is successful he does not suffer the -4 Penalty.
Prone and helpless even on a successful save? Be careful, that opens up Coup de Graces from allies.
Also, -4 penalty on all rolls? It should be more specific (ie: Attack rolls, damage rolls, skill checks, ability checks, saving throws, caster level checks, concealment checks, whatever you want it to affect). I don't think anything else in the game gives a blanket bonus or penalty to all rolls. As written, I don't think it even technically affects checks and saving throws, but does modify things like Hit Dice rolls and miss chance percentile rolls.
Charming Stance
The Feline Way (Stance)
Level: Swordsage 8, Warblade 8
Prerequisite: 3 Feline Way Maneuvers
Initiation Action: 1 Swift Action
Range: Personal
Target: You
Duration: Stance
Saving Throw: Willpower Negates
While you are in this Stance choose 1 opponent within 60' to target. He must make a Willpower Save or be considered Flat Footed until you target another opponent or switch Stance. Cause you're just soooooo kyooot...
What's the action to select someone to be charmed by your kyoootness? If someone makes the save can they be affected again? If its a non-action, the save doesn't matter because you can just switch to another opponent and back to your original target over and over again until it fails the save.
Charming Stance is missing the save DC. Unlike spells, maneuvers do not have a generalized DC formula. The DC is usually 10 + maneuver's level + some stat bonus (I'd guess Dex for this school, although Anklebite and Bitin' the Berries allow Str or Dex which should be okay as well).
Flurry
The Feline Way (Counter)
Level: Swordsage 5, Warblade 5
Prerequisite: 2 Feline Way Maneuvers
Initiation Action: 1 Immediate Action
Range: Personal
Target: You
You may initiate this Maneuver whenever an opponent provokes an Attack of Opportunity. Your AoO does +8d6 damage as you swarm him with blows.
This should specify that your opponent has to provoke an attack of opportunity from you, not just from anyone.
Flying Tackle
The Feline Way (Strike)
Level: Swordsage 3, Warblade 3
Prerequisite: 1 Feline Way Maneuver
Initiation Action: 1 Standard Action
Range: Melee Attack
Target: One creature
You initiate this Maneuver as part of a Charge Attack. If you successfully hit your opponent you do +4d6 damage and you both end up Prone.
A charge is a full-round action, leaving no room for the standard action to initiate this maneuver. Just change it to a full-round action to initiate and have a charge as part of it.
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