Honestly, I don't see a Pokemon themed one working well, unless they have a low price for the figures.
Right now, the Jakks Pacific figures that they make are crappy quality plastic and retail for about the same price that the Skylanders are at now. I've seriously wanted to get figs of Tepig and Zekrom for my collection, but I can't justify spending that on some dinky figure that I KNOW I can get something better with the same amount of cash.
And then those inevitably get moved to the reduced price aisle. And although
something like this has happened before, the prices were just too high for the TFG figures. (Even though they were beautiful looking)
Skylanders hit it good in the $7.99-$9.99 range. It's just enough to not set people over the edge with "It's HOW MUCH?!" and not so cheap that they'd loose money on it. If they do have a sequel, they'd have to keep them in the same price range or lose people over the prices.