Zions (ZION) could be a solid choice for investors given the company's remarkably improving earnings outlook. While the stock has been a strong performer lately, this trend might continue since analysts are still raising their earnings estimates for the company.The rising trend in estimate revisions, which is a result of growing analyst optimism on the earnings prospects of this financial holding company, should get reflected in its stock price. After all, empirical research shows a strong correlation betwe ...