Sandisk have a 128GB microSDXC card developed (spoke to a Samsung representative a while ago), unfortunately there is no confirmed ETA for that card.
The Microdia cards (when original) seem to be rebranded Samsung cards, no clue whether the 128GB cards on Amazon are legit, the price suggests they might be fake.
Good to know. I'll keep an eye out on the US/Canadian amazon sites, and see if they pop up there. At least if they're fake it'll be easier to return.