American Express Company (NYSE:AXP) looks to justify new price targets on the stock from analysts when the company reports third-quarter financial results before market open Friday.Here are the earnings estimates, what analysts are saying and key items to watch.Earnings Estimates: Analysts expect American Express to report third-quarter revenue of $18.05 billion, up from$16.64 billion in last year's third quarter, according to data from Benzinga Pro.The company has beaten analyst estimates for revenue in t ...