Is it a mirage? A myth like El Dorado? A mass hallucination? The power of Steve Jobs’ well know RDF? Collective wish fulfillment? All we know is . . . it’s the rumors of the Apple Tablet computer.

Rumors of an iTablet have been floating around almost since the moment the iPhone came out two and a half years ago. But in the last few months, things have really gotten out of hand, and it seems like we’re hearing rumors practically every week. (My own–admittedly lame and third hand–sources simply laugh at our gullibility.) Let’s review:

In early December, a number of sources reported that Apple’s manufacturing partners were gearing up to release . . . some mystery product or other. “Must be the iTablet!” hyperventilating Apple fanboys everywhere exclaimed, hopefully. (I’m not an Apple fanboy, but I’m definitely hoping to see this product.)

Then today, two new reports in quick succession. Earlier today, the Silicon Valley Business Insider reported that Apple was giving a heads-up to developers to do a demo in January:

Apple has been telling some app makers to prepare apps for a demo next month, according to this source. “They’ve told select developers that as long as they build their apps to support full screen resolution — rather than a fixed 320×480 — their apps should run just fine,” our source says.

Next up was a report from the Financial Times about Apple renting out space for a big demo scheduled in late January:

The company has rented a stage at the Yerba Buena Center for the Arts in San Francisco for several days in late January, according to people familiar with the plans. Apple is expected to use the venue to make a major product announcement on Tuesday, January 26th. Both YBCA and Apple declined to comment.

So to sum up, the rumors boil down to developers being warned about a January demo, and manufacturers getting prepared to ramp up in February, which based on the iPhone release schedule (it took about six weeks to turn around the manufacturing and get the devices in stores) would seem to point to a March release of something. Which fits in with yet other rumors for a Spring/First Quarter 2010 release. (I might even mention even more rumors of Apple negotiating with CBS and Disney over TV show subscriptions. Streaming commercial-free TV on an iTablet! Yeah, that’s the ticket!)

So there you have it. Solid information, or the feverish ravings of desperate nerds? Who knows? We’ll have to wait a month to find out. But I keep reminding myself that until January 2007, Steve Jobs kept vehemently denying rumors of Apple building a phone, too.

So hope or dread late January, depending on your level of iTablet desire, my friends. I know which category I fall into.