First of all, I have to say I am enjoying DNF thoroughly - so much so that after three days of owning LA Noire and Duke, LA Noire is still sitting on the shelf, even though I'm desperate to play it.  Really I ought to load up DOS Box and play good ole' fashioned Duke Nukem 3D as a comparator - or one of the recent methods for playing it on later machines... 
 
The fact is, no it's not the most amazing game ever to grace the XBOX, but the long development cycle probably harmed the game more than helped it as I've discussed before, plus the hype over it - partly due to the eon long development cycle hasn't done it any favors.  However if pressed I could come up with some criticisms, based on two hours of play.
 
1. The plot isn't going to win any Oscars.
 
2. The voice acting in places isn't amazing, it serves it's purpose - but it's not genre defining.
 
3. The levels up to the Pit Lord achievement can seem very restrictive.  There are a lot of blocked pathways and locked doors, They try to give you a feeling of a broad, large open city - but you are very limited as to where you can explore.  So far it's been fairly linear with some back-tracking.
 
4. The Load Times... Numerous times you find yourself watching a loading screen printing hints at the bottom with the level title at the top.   Some times you seem to be staring at this screen for far too long...
 
5. The enemies, they aren't that varied so far, there are essentially melee enemies, shooters and shooters who can teleport up to this point in the game.  I expect more will appear but hey - I'm trying to give game play criticism.
 
6. The weapons, You really only have had access to less than half a dozen weapons by the end of the pitlord achievement.  Most are effective enough, but there's not a great deal of variation between their strengths and weaknesses - although there is some so... The fun things, pipe bombs and trip mines are just starting to appear by this stage.
 
7. The environment interactions are great, but giving you a few makes you want to try to interact with everything... Which you can't, which can get frustrating...
 
All this aside - it's fun!  I like it, I find it very accessible.   I wouldn't like to give it a rating out 100 yet, but I certainly think it works well as a game.  I don't share the view that the graphics are awful and the frame rate sucks... Maybe it's because I'm not a Call of Honour or Battlefield of Duty or whatever fanboi - maybe they do graphics better than Duke?  I don't know... Could it be because when I started playing games in about 1982 we didn't really have anything you could describe as graphics and audio... More like sprites and beeps... I grew up being eternally more interested in game play than the cinematic properties of games... I agree that these things are important now, but at the same time I can't help but think, beyond a certain level - they don't actually matter.  As long as these things are not so bad that they negatively affect immersion then I genuinely think game play is far more important.  Game play is what makes or breaks a game in my opinion, the rest is icing on the cake, and that's why small independent developers can sometimes succeed, because innovative core mechanics although harder to develop, are not always expensive...
 
Some people might think Duke Nukem Forever should have shown more innovation... But to that I disagree also, games are like any technology - there's only so much innovation people can take at a time.  People want a product they are generally familiar with, but which provides additional elements.  Whenever something completely off-wall comes out, that pushes every boundary - it often fails.  Not always - Minecraft is a recent example, Populous is an older example, both do something quite unfamiliar and offer a fairly new experience in terms of game play.  I think with FPS it's harder to push a great deal of innovation to an FPS audience, because it's such a saturated genre... It has been since Wolfenstein 3D... There was a new one every week it seemed at one stage, what with Wolfenstein, Doom, Heretic, Rise of the Triad, Tech Wars... They were spilling out of studios at a rate of knots... 
 
And we have some very high quality titles in the genre at the moment.   People expectations for FPS are probably higher than most other genre.  I think it's probably a very unforgiving genre to develop in.  DNF brings a little to the table I think, with the mini-game style distractions and environment interaction... I'll probably have formed a more detailed opinion when I've finished it.