A new generation of iPods is coming and the cat-and-mouse game that Apple's (AAPL) legal department plays with the rumor sites in advance of a product launch is now fully engaged.

On Saturday Apple issued a cease-and-desist order against MacRumors, demanding that the site remove a video purporting to show a click-wheel driven iPod interface that lets users scroll through a photo collection with the "coverflow" visual metaphor pioneered in iTunes.

On Wednesday, Apple legal asked 9to5Mac -- and later Gizmodo -- to remove a fuzzy photo of five squat devices that the sites claimed were prototypes of next generation iPod nanos. Both complied, although as of this morning the original photo can still be seen here, here and here. Gizmodo interpreted the cease-and-desist order as confirmation that the photos were genuine, but Apple has been known to leak and then demand removal of bogus product shots, just to throw reporters off the scent.

The most useful intelligence so far comes today from Kasper Jade at AppleInsider, who posted a detailed report early this morning pulling together everything he's been able to learn about the next generation of iPods. According to Jade, Apple in mid- to late-September will introduce as many as four new models, most if not all using NAND memory rather than hard drives to store music, videos and other data.

The flagship video iPod and iPod nano, according to Jade, will run a variation of OS X rather than the Pixo-based software that drove the first generations of iPods -- the culmination, as he puts it, of "a multi-year effort ... to form a new platform of digital devices around the common core of [Apple's] legendary operating system software and expertise in industrial design." (link)

Jade's sources in the Far East, where the iPods are being manufactured, also suggest that there might be an element of truth to some of the spy photos and videos that Apple legal has been suppressing so assiduously.