So far for me it seems like the best gran turismo yet - and i haven't really liked any since 3 (my first one). GT4 was just confusing, and GT5 just wasn't very fun - that's not even counting the weird menus and loading times. I think with that one polyphony might've forgotten they were making a game for the general public and not just themselves.
The graphics aren't really any different to 5 (not a bad thing) but I really don't understand why polyphony keep insisting on upping the resolution - the hardware just can't do 1080 pees at that frame rate and the tearing they resort to is simply unforgivable (haven't heard of triple buffering??). I force my display to 720p which makes it go away for the most part and the lack of tearing more than makes up for any loss of resolution which is barely noticable from the couch anyway. The blocky/shimmering dynamic shadows are also a bit more than the hardware can deal with but the dynamic time and weather it enables makes it an acceptable trade-off. I only drive using the bonnet-cam so I couldn't care less about the internal car modelling and TBH GT3's cars looked good enough from the arse-end which is the only thing you can see when racing. I don't really mind GT's sound engine or even music for the most part either.
The menus are mostly better apart from the tuning screen with it's expanding tabs although most of the other menus are a lot better. Much quicker too and global short-cuts let you change or re-tune your car anywhere rather than having that shithouse partitioned garage from GT5 (where standard cars are segregated). A weird niggle is that it doesn't remember some of the driving options when you change cars. Collisions are still modelled on a plastic canoe but I suppose that's better than just ending the race in a shower of broken glass and burning rubber that a true simulation would demand, or god-forbid adding some "sands of time" to rewind.
The introduction to the game (first few races, not the movie) is more gentle and the annoying license tests are a lot easier and fewer in number. Having the racing line from your friends pop up is also a nice touch - "asynchonous online" could work very well for this game and I think could well be the killer-app for Drive Club if it can reach a critical mass. The economy seems to be more newbie friendly too - GT5 had me re-running shit-box races over and over just to be able to afford a couple of upgrades to beat the next shit-box race. So far i've only re-run races to get a better time, and for the first few races it only takes one or two tries and by then I had enough credits to upgrade a bonus car to finish all of the novice class races easily. A couple of the current seasonal events give out nice cars for little effort too which is more than enough to get established but even the shit-boxes have a bit more get up and go which makes the early races less of a chore. Apparently it has micro-transactions although I haven't seen where.
I guess the most important part - the driving - just feels way more "fun". I think the tyres just feel a bit grippier and don't overheat as much or for as long. It seems more possible to recover from a loss of traction rather than just turning into an uncontrollable slide/spin. And you can finally roll cars - no more weird elastic which keeps the car from flipping over. I think they toned down the slipperiness of the non-road surfaces for the beginner cars and maybe they tweaked the learning curve a bit to make these more enjoyable to drive. I know it's supposed to be a simulator but it definitely is a game first.
Despite the number it feels like a more rounded game than any of the recent ones and would be the best entry point to the series i've tried. It doesn't take the 'simulator' sub-title so seriously that it ruins the game part of the game.
And yeah ... Bathurst ... at night.
Update: Been putting in a few hours every few nights lately. Yeah the economy is way better than GT5, I somehow ended up with 1Mcr from some 90 second time trial in the seasonal thing. So much less (actually none) grinding needed compared to GT5 - thank fuck for that.
Some of the tracks suck a bit, but that's just the track. e.g. silverstone or the indy track; too flat and the actual track doesn't always follow the marked lines on the road so you have to follow the map otherwise you run off (pain on a time trial if you're not familiar with the track since a run-off == disqualify). And the tracks being so sucky put you off wanting to learn them. OTOH some of the tracks are pretty good. I did a lot of grinding in GT5 on Rome with the 4x4 seasonal truck race and so that's become a bit of a favourite, I always liked Trail Mountain (that straight up the tunnel), and there's really nothing at all like Bathurst at dawn or dusk. During the race there's some weird dithering on trees and on replays you notice how they are low-depth sprites but given they fit the whole forest on there it's pretty forgivable. At least the gum trees actually look like gum trees too - which is pretty rare in racing games given how distinctly different they appear to other trees and the milky way at night is pretty impressive from the southern hemisphere. It's a pity they don't have the original layout before they added the dog-leg at the bottom of conrod straight, but I guess 'licensing' wouldn't allow that. The Matahorn is also quite a bit of fun in a light nimble car although it's pretty easy to over-cook it on the down-hill bits.
One annoying thing is that it only runs in NTSC timing - no 50hz output on HDMI. This is pretty sucky because those extra 4ms would help with the screen tearing a great deal and I just don't see why we need to be subjected to some legacy timing from an ancient american video standard. I know i'm probably going against the grain from 'gamers' who think otherwise but they are just ignorant and ill-informed.
Hopefully the seasonal events start including races - time trials are pretty boring and it's starts to become 'not a game' when one simple mistake requires a whole lap to fix. Although at least for the car prizes you only need to do a single clean lap - regardless of the time - to win the cars. If it was the first GT ever I could understand all the time trails to some extent - it's a bit of a training exercise to be able to drive properly - but it's no.6 (+ all the prethings) in the series.
I was pretty surprised to see how Forza on the xbone uses PS2 era rendering techniques - fixed shadows (actually even worse, all shadows project directly down from the videos i've seen), fixed time of day, no weather, really basic textures and 2D crowds (oh dear). Because the views in car games are quite predictable they are always able to push better-than-average graphics at high frame-rates and the car models are getting so detailed they seem to be at a point of diminishing returns. But I think there's an awful lot left for future games; GT already has weather and dynamic shadows, driveclub improves on the shadows, adds 3D trees and volumetric clouds. Future games could add procedurally created seasons or even dynamically created landscapes that grow and age. Better water modelling (puddles, flowing water, and not just 'wet'). Not to mention VR stuff. I think the car models are good enough (more than good enough TBH), but there's still enough possibilities that no amount of FLOPS will ever exhaust them.