Realbiker, I think you haven't met Joe Murray yet?
If you've met both him and Gary Fisher, you'll understand how one come sup with VooDoo's, and one with Genesis.
When i bought my first VooDoo in '97, the toptubes were regarded as longish, I used a 140mmx0º stem on that bike. Genesis was just 2" ahead of the rest, it seemed. While VooDoo hasn't changed much over time, Genesis is still here, and has set a trend towrds longer TT's. and yes, on my Fisher, I use a 90mm stem. It's just that for the KM, Surly added quite a bit of TT to their 1x1. Salsa more or less did the same.
VooDoo's still quite 90's, although I think the largest sizes did gain a handful of mm's.
I must say I share you longing for longer TT's, I don't think I'll ever buy something under 630mm again, or it'll have to be something Behemoth-like and beyond.