Here's my current "three day wild guess" on what we'll get for the new iPods:
iPod nano
Same general shape as current 4G nano, but will switch to true 16:9 aspect ratio LCD display. Capacities will be 8 GB, 16 GB, and possibly 32 GB. May or may not get built in camera.
iPod classic
Looks identical to current 120 GB model, but will get higher-capacity single-platter 160 GB hard drive and a menu display system similar to that of the current 4G nano. This will be the last of the hard disk-based iPods.
iPod touch
Essentially an iPhone 3Gs minus the cellphone functionality, will be available in 16, 32 and 64 GB versions.