1) apple have spent millions developing multitouch. Really, lots and lots of money. From what I've seen, it makes for an amazing interface. They have to have plans for all that R&D other than their new uncertain product.
2) Multitouch it's just the interface, no one has bought the iPhone purely for the interface, it's been bought for the whole package, phone combined with iPod, combined with internet, wrapped up by apple with a nice slick interface.
3) IT'S JUST AN INTERFACE, WHICH HAS NOTHING TO DO WITH THE CORE FUNCTIONALITY OF THE DEVICE
4) current ipods don't detract from iPhone sales, why would they? But they've both got video and music and photos built in? Yet they still don't compete with each other? But how could this be?
5) The iPod is now old and in dire need of updating, yet it is still whooping all the competition.But it wont for much longer without a serious revision. Oh look, they happen to have this multitouch technology laying around, they've already developed and paid for it. Should they just leave it alone, or use it.
6) With multitouch, iPod will drive iPhone sales. Millions of people own an iPod, a very small few own an iPhone. When people try out their new multitouch iPod, they will think "wow, this is really nice, maybe I'll take a look at that iPhone"
7) apple tv shows us that apple is looking more towards the content driven hardware sales. They need to have a credible portable video player, to get people to buy more content; when people have more content, they will look more seriously at apple tv. Therefore multitouch large sceen iPod will also drive apple tv sales. The only way to get a credible video player is to make that screen larger, but they need to keep the current unti size the same to keep it portable. A screen taking up the entire front of the unit is the only way to go, discounting a flip open player, which just aint going to happen. The only way to make the video full size is to have touchscreen controls. Or put them on the side or back. I think we can rule out the side option. The back is possible, but I think too many people would have issue with controlling it.
ERGO MULTITOUCH IPODS ON THE 5TH FTW