From every hint, from every rumor, from every direction it seems like some sort of Apple tablet is a done deal. We'll know for sure Wednesday, probably after a "one more thing" from El Jobso.
If a tablet is announced, I'm trying to figure out if I will buy one. I already have a Mac Pro desktop, a very serviceable MacBook Pro, and the latest 3GS iPhone. For reading I have a Kindle, and the 2 week battery life is pretty hard to beat. It's small, it's thin, and compared to the rumored cost of the Apple tablet, it's likely a lot cheaper.
But I think the dilemma will be even rougher on MacBook owners, who already have a nice small information appliance they can take anywhere. Looking at it as objectively as I can, there doesn't seem to be any room in my life for a tablet. It seems like the cure for which there is no disease. I get my email easily away from home any number of ways, and the iPhone is so good at so many things I don't take my laptop on the road as much as I used to. If, as expected, the tablet is smaller than the MacBook, maybe as thin as the MacBook Air, and significantly less expensive than either of those, it will turn some heads, but probably not mine. No way.