I think that, as with any Apple product, treat everything with skepticism until the actual product hits stores. But it would be rash to immediately call these photos fake.
There's could be any number of reasons why the inside would be white while the outside was painted red. I really don't see Apple's stopping production in at least one assembly line to mix up a special batch of red polycarbonate and manufacture exactly two (2) red MacBooks. Perhaps if/when the product launch happens and a production run of several thousand (or maybe tens of thousands or hundreds of thousands?) happens, we'll see the real thing, and maybe then the entire casing, keyboard and all, will be red.
Then again... I personally like the white interior, and wouldn't see myself enjoying typing on a bright red keyboard very much. Maybe a red interior just doesn't work well when one actually happens to want to use such a computer for an extended period of time. Of course, this is coming from someone who thinks the silver finish on the keyboard of the MBP is tacky as all hell, but I got one anyway because that's the only color they come in.
Also note that not ALL (red) products are
totally red: the Red RAZR, for instance, still retained its metallic silver keypad on the interior.
At the end of the day, I have my reservations and skepticism regarding the (red) campaign as a whole in terms of the philosophy behind it and whether it's
really effective, but that's a whole other discussion for another forum.