Ebay: a promising big picture Don't forget eBay. Google, Apple, Amazon, and Facebook may be the so-called "four horsemen" of tech. But the stoutest survivor of Web 1.0 - eBay's market cap is $72bn - remains as relevant as its flashier peers. Ebay's Marketplace segment, a bit over half of total revenue, is no longer just an online flea market. You can still bid on that antique vase from that guy in Sioux Falls, but you can buy from Toys R Us, too. And its PayPal payment business is much richer, figuratively and literally, than when in 2001 it was acquired to help buyers and sellers on the website feel safe about paying over the web. PayPal processed $145bn transactions in 2012; eBay's own sales volume was less than half that. Electronic commerce is a $1tn market, and PayPal touches about 15 per cent of it. And PayPal is poised to thrive in mobile commerce - the next big thing, given PayPal's reputation for safety and certainty on the desktop. What is more, with 128m users, PayPal believes it can leverage that installed base to touch the entire $10tn retail market. The company has established partnerships with Discover, NCR, and a series of large retailers such as Home Depot so customers in stores will increasingly be able to pay via their PayPal account. The big picture would then seem promising. But on Wednesday eBay gave disappointing second-quarter revenue guidance. Shares fell 3 per cent on cue, but they are still up an impressive 140 per cent over the past three years. And investors should take the long view. The company is projecting three-year revenue growth at PayPal above 20 per cent and company-wide long-term revenue and earnings growth about 17 per cent. Sure, earnings should be growing faster than sales, but building market share may be worth sacrificing a little profitability.