Yes, but with some caveats.
Online reviews in particular want to be up quickly and generating site activity and hits. For many games, with reviewers getting the game early, this isn't too much of an issue. But some games really need a long time to judge - GT5 being one of them - and therefore early reviews are almost certainly based on a far higher degree of assumption from a relatively small time with the game.
I've had GT5 since Monday (yah) and online only can on yesterday. What I can tell you is the game has a lot of content and a lot of that content is tied to being unlocked over time. For sure, reading some of these reviews its apparent that they've only taken a fairly cursory view of some areas then made assumptions.
I note for example most reviews are focused on the traditional driving mode vs the mode where you give instructions to a driver. Trying this mode myself I can see it's going to take a while to get to grips with.
Then there are the special events which only unlock slowly but contain a lot of new stuff - karts, Nascar, etc.
I'd say trust the reviews, just be sure to understand that in this case - as with other titles that are very broad in modes that also have deep levelling - that you are getting impressions and assumptions based on relatively little time vs what you will be putting in if you really want to get the best out of the game.
TBH I doubt it'll matter. GT is in some ways review proof I suspect.
Personally, I'm amazed that even playing it a fair bit since Monday there are so many areas I keep pushing back having a look at due to time. I've barely played with the course editor, or tuning cars, for example.
Try to be reasonable... its easier than you think...
