Whatever is released, it's guaranteed to upset people that have already made up their mind on what Apple *should* release. Apple would be insane to release Snow Leopard on a tablet due to the usability issues, so anyone wanting a desktop-like experience will cry that Apple is epic fail.

However, here's what I think is more likely, and I'd line up on day one to get it:

- General-purpose *browsing* device. Web browser, ebook reader, magazine reader. I can imagine people getting their Vogue or FHM subscriptions through iTunes, and using their tablet to flick through the magazine. (Fully interactive, hyperlink enabled magazines, mind you, not just static PDF's).

- Very slim, shiny hardware. Thin as an iPod Touch. Standby time counted in days. i.e. low-power ARM based CPU

- App Store for application delivery. Why break something that ain't broken (for Apple and customers at least. Dev's will still hate on it).

- One full-screen app at a time UI. Not neccessary limited to running one app at a time, though. Think full-screen office apps, powerpoint viewer, video players. Maybe use existing iPhone apps as widgets.

- Front-facing video camera, for iChat / Skype videoconferencing.

- Games. The iPhone has been massive for handheld games, this could be even better.

The above would be perfect for 80% of home users. Apple can position the MacBook / MacPros for professionals that need all that complexity, and the tablet for everyone else. With a stand and wireless keyboard / mouse, it would also make a cheap home computer, but it would be ready to pick up and go with you at any time. No complicated file system, no hard to use UI, no settings to worry about. Just works.

I have been through exactly the same thing, and NTFS is the way to go. My main machine is a Mac, but I format all my USB drives as NFTS (through NTFS-3G FUSE). Though this is slower than formating as FAT or HFS+, it is so much more portable, it wins out. Windows machines can read them. My WD TV box can read them. My Mac can read them. They can store more than 4G per file (indeed, I have all my DVD isos on them). Ok, they can't be read on other macs without installing NTFS-3G, but I've yet to need that. For me, I've never had any problem with NTFS-3G , it's extremely reliable.

I've been using the eee version of Crunchbang. http://crunchbanglinux.org/blog/2009/01/18/crunchbang-linux-81002-released/ Works flawlessly with full driver support, is very fast, and isn't brown.

I've got first hand experience of this. My close friend was accused as part of Operation Ore. He came around sobbing one afternoon, after the police had crashed into his flat at 7:00, searched through all his stuff, took all his computer equipment (which he needed for his work, and contained irreplaceable files) and took him down the station.
That night he slit his wrists.
*Luckily* another friend went round there the next morning, and found him barely alive in a pool of blood.
Since then, after several months of recovery, he's lost his flat and had to file for bankruptcy. And yes, he was one of the victims of credit card fraud.

That's just one of the reasons I've since moved from the UK.
Don't let anyone tell you the UK isn't a Police State - they're too blind to see the reality.