King of the (Stock) World: After ceding its Wall Street crown to Nvidia, Apple has reclaimed the title of the world's most valuable public company, and the shift says as much about the mood on Wall Street as it does about Apple itself. Chip stocks have been especially volatile lately, which is one reason a "traditional" IT company like Apple looks better positioned to ride out the turbulence. The company's valuation has grown more than tenfold as Nvidia supplied the GPUs needed to train and run today's most complex AI models. Apple CEO Tim Cook is expected to step down soon, handing the reins to senior VP of hardware engineering John Ternus. Cook led Apple for 15 years, and Ternus is reportedly set to carry on his former boss's approach to major financial decisions, including AI infrastructure spending.