I'm unclear about a few things, though. The spell says the Phantom Steed "won't attack". I'm assuming this means that the entity created by the spell has no attacks of its' own, not that you can't fight at all on a Phantom Steed. If you cast the spell for a fighter with a lance, mounted combat, and spirited charge, there's no reason he couldn't charge into combat as he would with any normal horse, right? It's just that this particular horse is quasi-real, has feet made of mist and will vanish at the end of the day...
Which leads me to the next question: does the phantom steed count as a mount for all the mounted combat feats? I'd assume stuff like trample or overrun is out; the phantom steed doesn't have an attack. But would a rider be able to use Mounted Combat to negate a hit to the Steed? Ride-by attack while "flying" at 240 feet? It is quasi-real, and the spell description gives stats for it (AC, hit points, etc). I would argue that feats and skills that effect riding a normal mount would apply here, too, within reason.
It's conjured with something that "seems to be a saddle, bit and bridle". Is it really a saddle? Could you replace the phantom saddle with a real military saddle, to help prevent falls? Or is it a part of the phantom that can't be removed?
Can the Phantom Steed run? A tireless flying mount that can cover 960 feet per round at a full run seems abusive, to me...
