Financial analyst Trip Chowdhry, who’s frankly got a hit-or-miss track record, put in train the rumor – spread in turn like a virus by Barron’s – that Steve Ballmer will turn up at Apple’s Worldwide Developers Conference in San Francisco June 7 and share the keynote spotlight with Steve Jobs for seven minutes.

It took Microsoft about 24 hours to tweet that “Steve Ballmer not speaking at Apple Dev Conf. Nor appearing on Dancing with the Stars. Nor riding in the Belmont.”

According to Chowdhry, Ballmer was supposed to talk about Visual Studio 2010, the latest rev of the Microsoft development tools, which is supposed to let developers write native applications for the iPhone, iPad and Mac OS as well as Windows Phone 7.

Maybe Apple needs a surprise considering the highly public loss of two prototypes of its expected iPhone 4G to the blogosphere, but didn’t Jobs just outlaw other people’s development tools or is that just a Flash edict?

And since Flash is on the outs with Jobs, people started speculating that Ballmer, or by Chowdhry’s lights his possible stand-in Microsoft server and tools chief Bob Muglia, could chat up Silverlight for Apple’s widgets, a rival to the verboten Flash.

All of this was seen as highly ironic considering Apple’s market cap passed Microsoft’s for the first time ever Wednesday, making it nominally the second most valuable American company after Exxon.

Guess it is ironic considering Microsoft had to loan Apple $150 million a dozen years ago after Jobs came back so it could stay in business.

The press caught up with Ballmer in New Delhi and he basically shrugged the upset off. Microsoft is a billion dollars more profitable than Apple – if he can keep it. Having just reorganized Microsoft’s phone-Zune-Xbox unit, he is going to try to accelerate plans rather than change directions.

Microsoft’s stock has pretty much been in a standstill position for 10 years.

• Apple vs Microsoft By the Numbers