Gran Turismo Mobile(PSP) - This is the reason I bought a psp, the videos have been shown to us prior to the psp launch, and many myself included thought we'd have seen this game in the first few months. Yet it hasn't been spoken of at all in a long time. Here is a video:
http://www.youtube.com/watch?v=jAfRA_4RcRQ
Sadness(Wii) - This game was first shown as a live action video of a woman in black and white. Personally I didn't even think this was a game, just a PR vid demnostrating how immersive the console is. yet we've not only gotten confirmation about this 2nd party company working on it, but they spoke at length on how the game is coming along. Yet we haven't seen media on it, and have yet to get a release date. So it seems rather allusive at this point. here is a video:
http://www.youtube.com/watch?v=gNjyw-D1YP0&mode=related&search=Alan Wake(X360) - This game looks amazing, possibly the very best graphics on the 360. With Max Payne creators on it, it seems in rather capable hands. Yet what always struck me as odd, is the mystery surrounding gameplay, is this an adventure game? Shenmue with a horror twist, or does this boil into a shooter of sorts more like Max Payne? The answer hasn't seemed to surface and it's launch date has been pushed to an undisclosed. time. Here is a video:
http://www.youtube.com/watch?v=0x1WX16vgf0
Anyway you can add to the list. These games I still believe are coming at least the last two. You can create a list of games that will no longer make it, but it's always weird when you feel you've been talking about a certain game forever and suddenly you realize you haven't heard a peep about it in months. It makes you wonder if it is going to dissapear.