Fighter had the most options of all the classes. They didn't have to worry with spells, or what armor they could choose for some ability.
Options in and out of combat, not just character build options.
Here are my observations from having played a warblade, as compared to my prior experiences of having run a fighter.
1) I have probably said this umpteen times, so just bear with me. A decent skill list (balance, diplomacy and tumble!), and enough skill points (4+int mod) to let you invest in a reasonable array of skills. It does not hurt that the warblade also receives a small number of bonuses from having a moderate/good int score, so you don't feel like you are wasting precious stat points (starting with 14 at 1st lv, you can eventually improve this to 20 with a headband of intellect+6, for a +5 bonus on a variety of checks, not really heaven-shaking, but still good to have).
Contrast this with the fighter, where you had to "waste" points just to raise your int to 13 or 14 in order to pick up expertise (since it was a prerequisite feat for quite a number of important feat chains). His skill list stank, and rarely ever saw use. He was basically useless outside of combat.
2) Lesser reliance on full attack. At higher lvs, the fighter is extremely reliant on using the full-attack action to maintain his damage output. Unless he can access a means of pounce (such as dipping in 1 lv of barb), he is at a disadvantage vs extremely mobile foes who can move after making a single attack (which can be a standard action such as a SLA). Conversely, the warblade can still consistently deal a decent amount of damage with standard action strikes like diamond blade nightmare, ancient mountain hammer or strike of perfect clarity, which allows him to take a move action beforehand.
3) Higher mobility. The typical fighter wears fullplate, which reduces his base speed to 20ft. Even with speed boosters like haste/magical boots, he may still be at a disadvantage vs faster foes. Likewise, difficult terrain (such as a blade of grass in his path) can hinder charging, further restricting the ease with which he can navigate the battlefield. It is amazing how tricky terrain can screw with PCs in ways that optimized npcs never will.
On the flip side, the warblade has the advantage with the shadow hand teleportation maneuvers (which he can readily access using the martial study feats, since they do not have prereqs). The ability to teleport 50-ft as a move/swift action is very useful, not least because it lets you easily move into a favourable position regardless of how cluttered the battlefield is, while still allowing you to make a standard action attack (or full attack, such as time stands still or feral death blow). Quicksilver motion also gives you an extra move action, so you can move+full attack.
It lets you ignore difficult terrain and more importantly, escape a forcecage, a spell popular with higher level spellcasters which can immediately shut down a fighter with minimal fuss.
4) Versatility. A fighter who goes down the weapon spec tree is locked into his choice forever. If you specialized in greatswords, and need to chuck it for daggers when attending a dinner party incognito, tough luck, 6+ feats just got rendered useless. Conversely, the warblade who opted to take this same weapon spec tree can adjust his entire selection on a whim. He can use using greatswords today, longspears tomorrow, a spiked chain the day after and morningstars when he expects that he will be facing skeletons.
And his maneuvers work with any weapon, even soup spoons. You don't get any cooler than initiating lightning throw to deal 10d6 damage to all foes in a line with the wooden toothpick you happened to be cleaning your teeth with.
5) Crappy saves. It used to be that the player controlling the fighter could expect to sit out just about every fight involving some sort of will saves. In dnd, most will saves usually involved some sort of debilitating effect that either disabled/killed you (if you were lucky) or turned you against your party (if you lucked out). If your party faces a group of mindflayers, expect to be stunned/charmed for the remainder of the battle. Ditto for reflex saves (to a lesser extent, since it typically involves large amounts of damage, rather than save-or-die effecys).
The warblade is not as vulnerable. Moment of perfect mind lets you make your will save with relative ease (since concentration as a skill is much easier to boost than saves). Same for action before thought (which combos nicely with a ring of evasion). Mind over body is less important (since it affects your strongest save, but since fort saves also include save-or-die effects, it helps to have the extra assurance).
6) Adaptive style lets the warblade swap in a new array of maneuvers as a full-round action, allowing him to rapidly tailor his list of maneuvers to best suit any given situation. Facing a dragon? Bring in moment of perfect mind (vs its frightful presence), emerald razor (touch attacks are a given) and action before thought (vs its breath weapon). Facing simple brutes like a hill giant? Swap out the save boosters and bring in more damage dealing maneuvers. Fighting a wizard specializing in rays? Wall of blades takes care of your crap touch AC. Moment of alacrity effectively gives you that lost round back. You should never be caught dead with a less than optimal array of maneuvers.
Meanwhile, the fighter is left using the same tricks vs every foe he faces, however effective/ineffective it may be. A tripper facing huge+ foes? Tough luck. Sunder master, but facing foes not wielding weapons? Too bad.
7) Iron heart surge. Because being hit with a waves of exhaustion or maze spell really sucks for anybody (especially since they do not allow saves). Pity it does not let you counter an immobilizing effect like hold person, but hey, I am not greedy.
8) The warblade's variety of maneuvers make playing him more fun overall. I don't just move and attack/5-ft and full attack every round. I move, use a swift-action boost, and initiate a cool maneuver. Then my foe attacks me, and I initiate a counter. Plus, tapping the maneuver cards to signal their use is just too nostalgic for an ex-Magic player like myself.
There are a few other minor reasons, but these are just the main advantages I feel that a warblade has over and above a fighter. Basically, martial adepts made melee fun again, by giving them the options normally restricted to casters, but without the hassle of accounting for slots.
