I'm thinking Jcase might have a variation of a prototype so they throw people off the track, otherwise anyone with a test device would be able to leak the exact specs without any doubts. There are probably many of both versions out there, hence the different leaks the past month or so.
I'm sure it is very possible to end up with a very great sensor 5mp camera, but I'm thinking they would go with 8mp just for competitive stat comparison tables against the iPhone4s. If it is a 5mp, unfortunately it is an automatic, "blah blah..., my iPhone4s is way better because it says 8mp...". I'm getting the galaxy nexus either way
I do hope for a microsd slot on the production device, it just feels more future proof and adding a nice little 32gb chip puts storage on par with the top of the line of that "other device".