The issue with laptops now is a function of space, heating, and power consumption. The high-end graphics cards now suck up as much power as the rest of the system, generate enough heat to require dedicated cooling systems, and are often wide enough to take two slots. Not laptop friendly at all.
ATI would have continued their back-and-forth with Nvidia till something came along to upset that balance, and given how hard it is to break into an established market like that, it could have been a long time.
What AMD wanted out of the deal was the ability to offer soup-to-nuts chipsets like Intel can do, to help them crack the OEM market for desktops. That's where the real money is, in the tens of millions of Dells and HPs and whatever, not the high-end enthusiast market.
It is entirely possible that AMD will swallow ATI and it will all be peaches and cream from Day 1. I can't think of any previous time in the IT industry where that has happened, but its possible.
The danger lies in there being technological, logistical and business issues that make ATI hard to digest. Consider that AMD has to focus on their core product right now, where they are seeing serious competition for the first time in a while. They have to do this at the same time they are making drastic price cuts in that same core product. They're going to be trying to produce a new product line at the same time the target OS for that product is going through a radical change with many new requirements. Simultaneously, they are going to have to integrate new manufacturing processes, re-organize the business, and still keep the stockholders happy.
I don't envy them. It's going to be real hard to pull off in the short term. It will be interesting to see what Intel and NVidia do to take advantage of the situation.