The Financial Times’ David Gelles reports that Apple will hold an event at the Yerba Buena Center for the Arts in San Francisco. They expect Apple to “make a major product announcement on Tuesday, January 26th.”

Citing Piper Jaffray analyst Gene Munster, David Gelles hints that a tablet will likely be announced at the event.

Dan Frommer has since published a piece on Silicon Alley Insider saying:

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.

According to a source who spoke with the Boy Genius Report, the Apple tablet is going to come in a 7-inch size. Their source didn’t know whether or not that was the only size, only that the 7-inch size is definitely coming.

Not to be left out of the fray, MacRumors has found evidence that Apple has acquired the domain name “islate.com” and TechCrunch has found evidence that Apple has trademarked the term “iSlate.” MacRumors, building off of TechCrunch’s findings, later found that Apple has the trademark for “Magic Slate” as well.

As Nick Bilton of the New York Times puts it:

But the icing on the cake comes from a current senior employee inside Apple. When one of my colleagues here asked if the rumors of the Apple tablet were true, and when we could expect such a device, the response from his source was, “I can’t really say anything, but, let’s just say Steve is extremely happy with the new tablet.”

Yet another recently departed Apple employee tipped me: “You will be very surprised how you interact with the new tablet.”

It sounds to me like John Gruber was right, the tablet will be a 2010 thing.

Update 1/1/10: MacRumors has uncovered another “buried” Apple trademark, this time for the term “iGuide.” MacRumors’ Arnold Kim thinks that the iGuide name could be related to the Apple tablet. However, I would just chalk this up as another one of those just-in-case-we-want-to-use-it trademark filings.

Meanwhile, Fox News’ Clayton Morris has “confirmed” Apple’s January event. Morris claims to have spoken with a source inside Apple that has confirmed the rumored January event. Also, saying that the event will focus on the mobility space.