Bukhari: vol. 6, hadith 514, p. 482; book 61
Narrated Umar bin Al-Khattab:
I heard Hisham bin Hakim reciting Surat Al-Furqan during the lifetime of Allah's Apostle and I listen to his recitation and noticed that he recited in several different ways which Allah's Apostle had not taught me. I was about to jump over him during his prayer, but I controlled my temper and when he had completed his prayer, I put his upper garment around his neck and seized him by it and said, "Who taught you this Surat which I heard you reciting ?" He replied, "Allah's Apostle taught it to me". I said, "You have told a lie, for Allah's Apostle taught it to me in a different way from yours". So I dragged him to Allah's Apostle and said, "I heard this person reciting Surat Al-Furqan in a way which you haven't taught me!". On that Allah's Apostle said, "Release him (Umar) recite, O Hisham!" Then he recited in the same way I heard him reciting. Then Allah's Apostle said, "It was revealed in this way", and added, "Recite, O Umar", I recited it as he had taught me. Allah's Apostle then said, "It was revealed in this way. This Qur'an has been revealed to be recited in seven different ways, so recite of it whichever is easier for you."
So seven different dialects maybe or just different
The next Ahadith shows that there were differences that were enough to fight for.
Bukhari: vol. 6, hadith 510, pp. 478-479; book 61
Narrated Anas bin Malik:
Hudhaifa bin Al-Yaman came to Uthman at the time when the people of Sham and the people of Iraq were Waging war to conquer Arminya and Adharbijan. Hudhaifa was afraid of their (the people of Sham and Iraq) differences in the recitation of the Qur'an, so he said to 'Uthman, "O chief of the Believers! Save this nation before they differ about the Book (Quran) ..." So 'Uthman sent a message to Hafsa saying, "Send us the manuscripts of the Qur'an so that we may compile the Qur'anic materials in perfect copies and return the manuscripts to you." Hafsa sent it to 'Uthman. 'Uthman then ordered Zaid bin Thabit, 'Abdullah bin AzZubair, Said bin Al-As and 'AbdurRahman bin Harith bin Hisham to rewrite the manuscripts in perfect copies. 'Uthman said to the three Quraishi men, "In case you disagree with Zaid bin Thabit on any point in the Qur'an, then write it in the dialect of Quraish, the Qur'an was revealed in their tongue." They did so, and when they had written many copies, 'Uthman returned the original manuscripts to Hafsa. 'Uthman sent to every Muslim province one copy of what they had copied, and ordered that all the other Qur'anic materials, whether written in fragmentary manuscripts or whole copies, be burnt. ..."
I wonder why there were different recitations,could it be that they were,well different.