I don't see this happening. The obvious issue is that an iPad isn't strong enough to run MegaGlest at a reasonable quality. Next is the controls issue. While doable, the touch screen is difficult for fast paced gameplay. It lacks the precision of a mouse (unless you use a stylus, but most don't). Finally, much of the positioning code would have to be changed to work for the iPad's screen. And I can't even speak for whether or not iOS has the technology needed to run MegaGlest (software-wise). And if we ever did come to support a tablet, I'd see Android as being a more viable option than the iPad. According to
this recent story, the iOS platform holds about 55% of the tablet market and Android is expected to become the dominant tablet OS sometime next year. Also, I'm not entirely sure about the size for most tablet games, but they generally seem pretty minimalist, which makes sense, since tablets have laughably little storage space (and designers charge insanely high prices to upgrade to the next storage size, as seen by how a 16 GB iPad is $500 while a 32 GB is $600). MegaGlest is about 250 MB, but with mods, can easily grow from half to one gigabyte. Display size may also be an issue. The smallest tablets are 10.1 inches, but 7 inch tablets are starting to look prominent (particularly with the Nexus 7). Finally, most mobile and tablet games are pick up and play. They usually consist of short, easily broken up levels. While there is some exceptions, they're a minority compared to the angry birds style of games. The average MegaGlest game probably takes about half an hour, though an hour or so isn't uncommon either. All of these make the tablet an unviable platform for a game like MegaGlest.
At any rate, we can't even get a Mac version of the game up-to-date, so I don't see a tablet version coming in the forseeable future.