I rather expected this might happen eventually...
The only time a late-game addition to a console's controller line-up ever does well is if it offers something particularly noteworthy over what else is available across not just the system's own platform, but the competing platforms as well. This is why the DualShock took off (two is better than one, or so the theory goes), and even then, you saw very few DualShock-exclusive titles on PS1. Just support-if-you-have-it titles, for the most part, until the PS2 came out with already-integrated dual analog sticks.
The 360, if it does get a Wiimote-esque, will likely not have a lot of support for it. Probably ports from the Wii will add support for it (almost definitely, in fact), but it won't ever be a mandatory peripheral for more than a handful of titles, and definitely will not be a must-own component.
Sky Render - Sanity is for the weak.
