I hear the browsing experience on the Instinct is pretty weak, but then again, on the HTC Touch it's nothing phenomenal either.
Apparently, the instinct is an open platform. Doesn't that mean that it's possible for Firefox Mobile to eventually end up as an application for the instinct? While it's more likely for it to be available for WinMo and Symbian, Firefox is open source as well. This would make it that much easier to port it to the instinct platform. Firefox Mobile looks interesting. It definitely puts touchscreen use as a priority.