Yeah, it's all up to Shangai for 2008 - and I'll admit not to be very optimistic. At best, they'll be able to sell a 3GHz Shangai in Q3 with 5% higher IPC than Barcelona. How is that competitive with Penryn, let alone Nehalem? If they do deliver, it'll be a very nice improvement over Barcelona at least - but that's not very hard, mind you.
If I had to take a bet, I'd say AMD's market cap will fall down to less than $3.2B within the next 9 months. Of course, market caps don't really matter, what does is actual financials - and I won't try guessing there, too many factors at play at many months out.