Thanks Ivastic.
Also, it's worth mentioning that the prophecy regarding Tyre (Ezek 26) was quite possibly written while the siege was in progress (see http://en.wikipedia....)#Early_history), and after Nebuchadnezzar had already been successful in his siege against Jerusalem...so it's unsurprising that Ezekiel would prophesy the same outcome for Tyre. What is surprising is that Nebuchadnezzar failed to deliver.
It would seem from Ezekiel 29:18-21 that Ezekiel acknowledges the (partial?) failure of the Tyre prophecy:
Son of man, King Nebuchadrezzar of Babylon made his army labor hard against Tyre. Every head was rubbed bald and every shoulder rubbed bare; yet he and his army received no wages from Tyre for the work he carried out against it. Therefore this is what the sovereign Lord says: Look, I am about to give the land of Egypt to King Nebuchadrezzar of Babylon. He will carry off her wealth, capture her loot, and seize her plunder; it will be his army’s wages. I have given him the land of Egypt as his compensation for attacking Tyre, because they did it for me, declares the sovereign Lord.
As for the Tyre prophecy, yes Tyre was later defeated by Alexander the Great, but it was never made "a bare rock" (Ezek 26:14) and was later rebuilt, despite what the prophecy claims. Even if you want to assert that the "old" city wasn't rebuilt, you still have to concede that it was partially rebuilt, and the only reason it has never been fully restored is because it is an ancient landmark and the old ruins are preserved. By the same logic, Jerusalem was never rebuilt because the old city ruins are still there today. Looking at Tyre today (quite a successful city), Ezek 26:17-18 make little sense.