Maurer Sohne make spinning coasters
A Helix as a tight circle of track (and when mixed with true free motion spinning cars (not those crappy Primaeval Whirl waltzer style ones) makes an awsesome experience).
An Immelman is one of these:
http://www.cwoaguide.com/parkupdates/200304/page2/pics/jan04-4.jpg
...so no inversions, just awesome famliy-friendly elements.
Also check out the video of the two bits I mean here:
http://www.inquisitivemonkey.co.uk/images/wdwmagic/dragon.wmv
Reverchon Spinning Coaster's are quite common now, (even Brighton Pier... I mean c'mon... BRIGHTON PIER!), so I'm really hoping Disney go for a better and less common make.