I don't think anybody cares - Halo 2 is not good enough a game for anyone to upgrade their OS and entire hardware rig just to run it - They can make it as pretty as they like, but the game just wasn't that great.
At the moment, the ONLY reason I want to play Halo 3 is to get closure on the story - That's *it*. This is not enough motivation to make me buy an XBox360.
I don't know what's happening with the gaming market; It seems like some magic has been lost over the years - Halo 2 and Half-Life 2 are both far superior to their predecessors technically, but most people I know think the original were more... 'fun'.
I often suspect it's the striving for graphical quality over everything else - Most games seem like they're built around the graphics engine instead of the graphics engine being built around the game!
Most of the games I have fond memories for are ones that have had "Moments".
e.g., in TIE Fighter, the part when I got ordered to take out a mine-field in an unshielded TIE Interceptor, and then all hell broke loose when I did...
In Freespace 2, when the Psamtik opens fire on the Belisarius (I was like "OMFGWTFBBQ!DidYouSeeThat?!

), when you meet the Ravana, and later the Sathanas. And who can forget "DIVE DIVE DIVE!!"

In Doom, the end of E1 is usually a memory for people - The whole build up of the level with the music, and when at the end you meet a Baron of Hell for the first time! (That roar it makes scared the shizzle out of me! Nevermind that they were quite wussy...

)
In Half-Life... well, it was pretty much the whole game

In Halo, two were where me and my friend managed to get two Warthogs deep into the Cartographer structure (Using many a plasma-grenade and some creative driving

), and that part that builds up to you meeting The Flood.
System Shock 2... definitely when you meet SHODAN.
In Half-Life 2 and Halo 2, I can't recall any such events that just burned themselves into my brain. I dunno, maybe I'm getting old and jaded or something, but they just didn't draw me in like the originals.
In more modern shooters, FEAR, FarCry and Pariah for instance... they were pretty and the AI was clever and stuff... but y'know? They just didn't grab me... well actually no, FEAR was pretty good... it's given me a pathological fear of little girls in red dresses for one thing...
