bartimaous u make very good points but here are my comments to each question:
1) project ego (fable (an amazing game for xbox)) was in development long b4 the xbox, yet it is an xbox only game. And they probably just started making halo 3, as u said halo 2 has only been out for 5 months (ish), so likly xbox 2 release game.
2) yes, halo2 has been out for 5 months (ish), and ues it is a great game , but its pretty much over b4 its started.
3) and yea they will probably screw round with the release date, but not to surprise, just to improve :P
But then again thats just my veiws, then again like i said, u make very good points.
You mess with the best, you die like the rest/ 2nd place is dead last /Halo Lord