I'd be very surprised if Sprint didn't use the Pre hype to require Simply Everything, or some Everything plan, as a "Pre condition" for purchase, just like the Instinct.
1. Won't work on my sero plan -- sorry, only reason I am with sprint is because they're cheap.
2. Mojo limits development of truely native applications -- if this phone doesn't have 3rd party nav apps, then I will be forced to pay for a subscription
I'm sure someone will post the first tether hack within 72 hours of the Pre hitting the streets.
3. No tether hack -- I use it a lot =(