These two watches are interesting limited edition Royal Oak watches done in honor of the 40th Anniversary of the Royal Oak collection. While not the only limited edition models for 2012, these are the two skeletonized versions and each come in platinum cases - a bit ironic to celebrate the famous high-end steel watch.
Audemars Piguet probably still sells more Royal Oak (including Royal Oak Offshore) watches than anything else in their range. If you recall, they released a slightly redesigned version of the basic Royal Oak watch for 2012 in a 41mm wide case. Up from 39mm wide, the new size is meant to be more modern. These limited edition models look both to the past and the present with one being 39mm wide and the other being 41mm wide.
To be honest, the Royal Oak collection is no stranger to skeletonization. It has been done before, but Audemars Piguet doesn't do it the same way twice as far as I can tell. The first model is the Audemars Piguet Openworked Extra-Thin Royal Oak 40th Anniversary Limited Edition. They use the term "openworked" versus skeletonized - they mean the same thing. As far as I can tell these watches aren't any more thin than the standard Royal Oak watch - so I am assuming the "Extra Thin" part of the name is there for marketing purposes because thin watches are in right now.
The skeletonization in the in-house made Calibre 5122 automatic movement is quite nice and certainly looks unique. There is a date window that goes around the dial - that looks more distracting in pictures than it actually is. There is a ring around the dial with lume-coated hour markers. Of course, there is also a non-skeletonized version of this watch for 2012 (but not with the platinum case). The skeletonization style is peculiar. It looks almost bubbly and a bit stylized. Good or bad, it is unique and with only 40 of them around, AP will have no issues getting them to eager customers.
The other model is 41mm wide and is the tourbillon version called the Audemars Piguet Openworked Extra-Thin Royal Oak Tourbillon 40th Anniversary Limited Edition. Geez these names are long. In this watch is the in-house made (and skeletonized) Calibre 2924 manually wound movement with a 70 hour power reserve. The movement is also available in a non-skeletonized version model, but aficionados like all the gear work. The skeletonization here is more traditional in style and is arguably the more desirable of the two models given the more aesthetically pleasing dial, larger case size, and more complicated movement. Though I know it will cost more than twice as much as the automatic.
These two platinum Royal Oak watches are pure Audemars Piguet DNA, and purely for enthusiasts. With just 40 pieces in each model (a low limited edition piece set for Audemars Piguet), it will be interesting to see the value these watches have in a decade or so.