There seems to be a fair bit of Cell-related news and new info floating around today
Remember the Toshiba demo with 48 SD Mpeg2 streams? Apparently they have 1 SPE handling a 1080i (1920x1080) stream by itself - so..6-8 1080i streams simultaneously on one chip? I certainly don't think any current desktop CPU could handle that (my 2.53Ghz P4 can't handle 1 without stutters).
I'm gonna go out on a limb here and say heatsink and fan?
It looks like it has a foam ring around it. Probably to keep the heatsink level when it's put on. That will compress and allow the heatsink to make contact with the die in the middle
I'm guessing that's just a PR shot. Like the pictures of hard disks with transparent cases. IMHO the real CELL packaging is unlikely to be open like that.