I love AMD, and have over the years built a number of PCs based around the various iterations of their CPU lineup. However...
I would not buy an AMD-based laptop, since I really don't believe they're as suitable, particularly where power consumption comes into play. Now, I've been out of the loop for a while and things could certainly have changed, but my instinct at this point is to back Apple's move to Intel.
No matter what, now that they're in the x86 space, it technologically leaves them open to the possibility of using more-or-less any x86-compatible CPU. And, as someone upthread already pointed out, OS X in other guises works on PPC, ARM, and who knows what else. I don't see how any of this cross-CPU development is a bad thing for Apple. Frankly, the only other OS platform with any greater degree of architecture independence is Linux. Apple's long since passed up Microsoft on this score, and this clearly gives them a substantial advantage.
Intel produces CPUs in mega volume. They give very good discounts to volume purchasers. Now, that being said, you'll note Apple doesn't drop their computer model prices as component prices drop for Apple, and while this does stand in contrast to what happens with other PC makers -- and isn't in and of itself necessarily the best thing for us customers -- it also means Apple is now positioned to be a very strong, very profitable company, and will likely be so for a very long time.
EDIT: Regarding Cell, the problem with it is that it's more of a specialized CPU, rather than a generalized one, and I don't think it would be as suitable for regular computers as it is for gaming consoles or specialized servers. No, I think Apple did the wise thing in not developing the Mac platform around it. That being said, it wouldn't surprise me at all to learn they have someone doing a Cell port, just to see if it can be done and how well it would work if it were done. In this business, you just never know...