If I remember correctly...
I work as a software developer. My boss writes his contracts stating that any machine (PC) that is replaced that has a hard drive, he will scrap the hard drive. At one point he had a ton of hard drives waiting for recycling, and it became my job one day to help.
I got to take apart a bunch of hard drives. Yay.
Really, it sucked, but if I remember correctly, those hard drive magnets were arranged where one end was opposite polarity of the other. The voice-coil of the head actuator of the hard drive was positioned by changing its voltage and its polarity, to move it thru the entire arc.
With that said - it is hard to say what is going on in the first picture, vs the second - because we don't know from the pictures (maybe more info is on the site?) what the polarity of the split ends are. Maybe in the first picture, he has two north pieces, then two south, then two north, etc - all the way around? But this doesn't make sense, because if you split a bar magnet (which is what these are, technically), you get two bar magnets - not two uni-pole magnets.
In the second picture, we just have the magnets arranged in a circular fashion, but we still don't know how the polarities are arranged.
Finally - where are the coils? In the first image, I can't tell if they are supposed to be placed over/under the disk of magnets, or around the edge. In the second, I have to assume that they are placed "over" the disk, simply because the outer edge would have little-to-no magnetic flux.
In both arrangements, you would end up with an AC output, and depending on how the magnets and poles were arranged (and how fast the disk was spun), that AC output would be of a certain frequency. There would also be dependencies on how the coils were arranged, wired, and synchronized; you could get anything from single phase to n-phase output - if wired wrong you could even potentially get nothing as the phases cancel out (and the coils would heat up and possibly burn out!).
It is difficult to say which, if either, would be better...