Here’s how these rumors get started. Someone tipped off Peter Burrows at
Bloomberg Businessweek
that Apple (AAPL) was waiting until after next week’s Consumer Electronics Show in Las Vegas to launch an iPhone for Verizon (VZ).

Apparently his anonymous source or sources didn’t give him a date, but by winks and nods they narrowed it down enough for him to write, in a story posted Wednesday at 5 p.m. EST, that Steve Jobs was likely to hold a splashy product announcement for the new phone “very soon, maybe by Valentine’s Day.”

By Thursday morning, a search for “Valentine’s Day iPhone” on Google News turned up 73 headlines, including the inimitable M.G. Siegler’s This Year, Apple Has Two Fangs To Suck The Blood Out Of CES.

Siegler’s theory is that the Businessweek leak is part of Apple’s perennial effort to steal thunder from the consumer electronics industry’s biggest international expo. He mentions two upcoming events in his headline — the Verizon iPhone and the iPad 2 — but the body of his story ticks off a whole mouthful of fangs, including:

• The long-awaited iPhone for Verizon
• The iPad 2, now reportedly in production
• Rupert Murdoch’s The Daily for the iPad, also due in January
• The launch of the Mac App Store, scheduled for Jan. 6
• Upgrades for the iMac and MacBook Pro, just down the road

For the record, Valentine’s Day this year falls on a Monday, not Apple’s favorite day for a special event.

[Follow Philip Elmer-DeWitt on Twitter @philiped]