Well there's a few ways you can look at it. In terms of the single player package, you can go 2 directions here. On the one hand, Halo 3, Gears of War or Call of Duty 4, there's 6 hours or so of cinematic plot-driven gameplay. For 6 hours, that's pretty damn good.
For Unreal tournament there's a highly refined offline multiplayer with bots of varying degrees of difficulty, tons of maps, all well balanced, several gameplay modes, all perfectly done. If I'm alone and offline, what game am I going to get more playtime out of? I've already played 6 hours of UT3 OFFLINE and had a blast the entire way through. I can fight bots here more than I'll play most games online against people. Literally, 6 months later, I will still be playing UT3 to fight bots in warfare mode or capture the flag vehicles mode. 2 years later, maybe nobody is online Halo 3 cause they all have Halo 4, but bots will be there in UT3. What about online now...? What other game has that? And online? If I ever get sick of the core gameplay, by that time there's going to be tons of mods to slap on my harddrive and try out new stuff.
I don't really know what to say though, in terms of your critique on the similarities to past iterations. It's the best of the series, and it looks amazing, and it's extremely innovative in the console realm. No console game before it will allow mods. No console game before it has these visuals combined with this huge scope and speed. To top it all off, this game pretty much guarantees that across all development studios, PS3 and Unreal Engine = fucking sweet. Part of the deal with Sony and Epic was that they'd update the engine so all the devs can get it. Can you imagine a better engine now?
But anyway... I mean we're all entitled to our opinion. But your major complaint seems to be that this game is too much like the last one, and in the same breath you compliment Halo 3. While the core mechanics of UT are the same, it's a much bigger visual leap and it's got the mods for consoles element that nobody else has, not to mention keyboard and mouse support which if you've played you'd see isn't even needed.
Then you say this generation is too much about graphics. Well, I've played Gears of War, and graphics is all it's got to be honest. At the time, it had the cover system, but Rainbow 6 Vegas and Uncharted both blow it away in terms of gameplay and then Uncharted matched and even bested it visually. What gears has is a visual edge over Rainbow and the fact that Uncharted has no multiplayer at all.
When you look at these games, they've all got something to them, but careful analysis concludes that for whatever purposes, 1 game wins in one aspect.
For offline multiplayer, that's COD4, no questions asked, for storyline, that's Uncharted/COD4/Halo 3/Resistance, for online multiplayer, that's COD4/UT3. For co-op splitscreen, that's Rainbow 6/Resistance/Halo 3.
Just picked up orange box, dunno where to put that, only played Portal so far, which isn't really a shooter. I can tell I'm not gonna like TF2.