I agree that bad news regarding Vx-478 will crush Vertex, short term. However, I think that the predictive value of Phase II success for Phase III success with the Protease Inhibitors has been very good for other companies.
I think the slow pace of development and announcements has caused individuals and mutual fund types to search for greener pastures (given the precariousness of the market and the fact that anything can happen (and will) in Biotech)
Another potential surprise with Vertex is VX-710 (in pivotal Phase II's). Basically they need to announce (with Biochem Pharma) whether this MDR Cancer drug is going into Phase III or into the waste basket (like their Hemoglobbin disorders program). According to some research I read these data should have been out in early 1998. If this drug moves on, I think their Cancer Program could get block-buster-euphoria status. If it fails, tighten your belt a notch.