By Arsheeya Bajwa (Reuters) -IBM on Wednesday recorded a slowdown in growth in its key cloud software segment, overshadowing booming AI-driven demand for the company's new mainframe that pushed third-quarter sales and profit above market estimates. The company's shares were down 5% in extended trading. Slower growth in IBM's cloud segment, housed within its software unit, raised alarm bells across investors betting heavily on Big Blue's ability to benefit more from booming demand for cloud services, as ...