I doubt if they'd use Aurora as a bomber: if anything it's more likely a reconaissance (if that's how you spell it) craft, as was the SR71. Bombers, cos of the amount of weight they have to carry, i.e. ordnance, are very heavy, and so can only fly at relatively low speeds at a relatively low altitude cos the higher you go, the thinner the air and so the more fuel you consume, which after a while becomes practically impossible in terms of pure physics. The SR71 etc, being spy planes (I can spell that!) only carry light stuff like cameras, and a couple of crew, so can go much higher and faster. If you look at the spec for the Blackbird it's about 100 feet long, narrow (again bombers have to be bulky) with massive engines and huuuge fuel tanks: about 70 - 80% of it's take-off weight would have been kerosene.
This is the reason stealth was so heavily developed: if you can't make bombers fast or high enough to avoid flak, you have to make them as low profile as possible. So it's much more likely, given the primitive anti-aircraft systems the Taliban had, that the US just used B-52s. Stealths only really come into their own against sophisticated systems, such as the Iraqis possess.
As for the fuel thing, the use of slush is a possibility, but from my understanding would still need to carry vast amounts of it to get really high or have a practical range(look at the space shuttle for example) and would still have the same problem vis a vis weight: it could well make it a deal faster though within the given parameters.
Perhaps we should just wait and see if Airfix bring out a model kit of Aurora (worked with Stealth!).