The update from 1.0 to 1.1 is really just tweaks, clarifications, and balancing. For instance, here is a blurb from their website about the update:
"...which adds +2 to the Move attribute of all species and turns Hull Stabilizers and Tractor Bays into Cargo Bay items."
All species have +2 movement, but diagonal movement has been disallowed. That is probably the "biggest" difference I have found, though there are others.
Resurrecting an old thread but I'm dusting off my 1.0 copy I've had for ... 7-8 years now and never played. Do I just need the 1.1 book to upgrade or is the whole box set changed?