I highly doubt it will be backwards compatible, but i think it shouldn't be too hard to port old programs over to the new calc (with the exception possibly of TI-Boy, which who knows what crazy hacks calc84 used). Also, the lack of an I/O port means that Steins;Gate won't have sound. I'm also really excited about the ez80 (and have been reading through the ez80 manual the past couple days). I'm also a little worried about the screen, but either way we'll still be much better off than with the CSE. I think this is the calc the CSE should've been. I'm also really looking forward to it and will definitely pick one up as soon as it gets released (and one's listed on Taobao).