@Ribs
Very good point, I was just about to say something similar.
First, read Wikipedia article (I know, I know, Wiki not accurate and so on but it serves as a place where one can get a summary of differing opinions)
http://en.wikipedia.org/wiki/Hadith_of_the_prediction_in_Sura_al-Rum#cite_note-Azmy-0According to that article it was Meccan hadith, not sure how that is asserted, problems are of course with the way the Quran was compiled, ie not written down in the form that we have it today nor recited by its entirety by a hafiz during the prophets lifetime. It was compiled in finality by Uthman, who burned all copies not similar to his copy. Also, the problem with hadiths being they were compiled 200 years afterward.
The timeline in the wiki article shows peace negotiations began AD 628, the time line of this verse is AD 615 (BH 7). That is 13 years, and I am being generous here, because it was in year 630 the war was conclusively and finally ended between the two empires.
There are some other issues, how did the Meccans get news from outside Hijaz? It would mean they weren't as encapsulated as one is lead to believe. Obviously, its an easy assertion to dismiss seeing how Mecca was a famous site of pilgrimage and trading. News would spread. Mohamed would know about the state of the empires. This however does not match Cheetahs point about empire building and conquests.
Other issue is these scholars interpreting some of the words to mean what they want. Like low lands instead of near lands, and the actual time it would happen, which according to the hadiths and scholars the maximum is 9 and Mohamed said 7. It was 13, or am I wrong?
Thirdly, this was a Meccan revelation. The believers would rejoice. Of course they would, Christians are our cousins, are they not? But this jovial mentality is somewhat contradictory to the Medinan verses, condemning Christians to poll tax and murder, amongst other things like eternal hell.
EDIT
Actually, the prediction in accordance to amount of years can be correct:
AD 622 (AH 1) Emperor Heraclius takes the field and defeats Persians in the Battle of Issus.
That was a victory, 7 years after the prediction. Within the 9 years prediction.