The rumors of an AI bubble have been exaggerated, it seems.Just hours after Oracle (ORCL 5.40%) fanned concerns about an AI bubble, investors were singing a different tune thanks to Micron's (MU 2.98%) first-quarter earnings report.The memory-chip leader crushed analyst estimates in its after-hours report on Wednesday, offering a forceful case that the AI boom is alive and thriving. Micron's revenue jumped 57% in the first quarter, accelerating from its previous quarter to $13.6 billion, which was well ahea ...