It reminds me, ironically enough, of Dragon Challenge from Islands. It always seemed at the point to where dueling was removed, to where that was on the chopping list. And that for a while, it seemed that nothing would kill it..until they did. I'm sure
@Mad Dog can explain that better than I can, but I get the distinct impression that Mummy..is in a boat similar to Dragon Challenge.
Nevertheless, I have no reason to doubt that Mummy won't leave. Much like Dragon Challenge from Orlando, it's a prime value space that can be used for something large. And would fit more with the Soundstage cluster than 22-25/28 for Nintendo.
That said, I shouldn't be talking more than I am, but I am not sold on Mummy staying for the rest of the year.