Nvidia have been banging on about their tegra gear for years.
Nothing has ever come of it, virtually nothing uses it afaik and the AC100 Toshiba netbook which came out recently and was reviewed by El Reg found that the software is years away from being usable.
Even MIPS has better software support.
So as far as ARM on the desktop goes... Lol, sorry, but it won't happen. Even in the NAS and home server/STB markets ARM is being pushed out by x86, specifically Atom.
It simply doesn't have either the software or the performance.
uh, you do realise that Project Denver is not Tegra. Their new chip is nothing to do with Tegra at all.