Amazon.com, Inc. reported blowout earnings on Thursday, revealing that its public cloud service business is not only on track to exceed $6 billion this year but is highly profitable and growing quickly as well. Amazon’s cloud footprint is so large that the company has been compared to the 1990s vintage of Microsoft, which dominated the PC industry so completely that it was prosecuted for antitrust violations on two continents.

“Amazon is at least a couple of years ahead of the market,” said Wikibon analyst Stu Miniman (right). “They have a sustainable lead. They’re growing, adding features and innovating at such a rapid pace that it’ll be tough to catch them.”

Still, the infrastructure-as-a-service business isn’t the same as the software industry, and there’s still plenty of room for specialized cloud providers to cash in on a tide that – for now, at least – is lifting all boats. “There’ll be some consolidation, but I think the market will evolve into two or three large companies at the top, a good-sized middle tier and a lot of small players,” Miniman said. “This is a winner-take-most market.”

About the only sure thing at this point is that Microsoft will be a strong contender in the public cloud, according to the Wikibon analyst. Google’s commitment is still uncertain and middle-tier vendors like Rackspace, Inc., VMware, Inc. and IBM will keep the pressure on. But there’s no reason to believe any of those players can challenge Amazon directly, and it’s too late for new competitors to emerge. “Anyone just starting out at this point doesn’t stand a chance against Amazon,” he said.

About the only competitive weakness for Microsoft’s Seattle-area sibling is its North America-centric focus. While the company doesn’t break out its cloud sales by geography, there’s no question that much of its revenue is domestic. In contrast, competitors like Microsoft and IBM have been global for years.

Still, Amazon is more than capable of diversifying its regional base, Miniman said. The bigger threat could come if the Internet itself becomes balkanized because of disputes over privacy, politics or government snooping, but such fragmentation would affect everyone pretty much equally.

And then there’s the fact that Amazon is Amazon. The company has a reputation as a ruthless competitor, and that could drive potential partners into the arms of rivals. “Amazon wants world domination. They’re scary good,” Miniman said.

Being nice has never been a necessary ingredient of business success, however. In fact, ruthless competitors usually win. Just ask Microsoft.