I'm in the half of that carrer mode and I really enjoy the game. Graphics are the weakest part of the game for sure. Most anoying thing is that you have to drive with lights turned off at dusk, because they were to lazy to implement dynamic lighting into the game. Car models have more polygons than NFS:SHIFT ones (checked) but again, devs were too lazy to even texture the lights. I still think that some tracks look really nice and at some points the game looks quite cool.
More important than graphics is of course the drive model and it's very good in this one. As for arcade game cars act pretty realisticly when all aids are turned off. You can clearly feel the difference between FWD cars and AWD ones.There is 13 rallys with 78 stages, which is very good comparing to any other rally game we had. Every rally feels different. Looking at the enviorement you can guess which country you are at. I didn't experniced this in DIRT 2, rainy Japan looked like sunny desert... every track looked like desert.
I think some tracks are a bit too flat and a bit too wide, but maybe it's just me. Another strong side of the game is of course that it's WRC licensed.
To sum it up, since there is not much competition in the rally games genre, I think WRC 2010 is really worth attention. If you are "there is no DX12, this game sucks!!!11" kind of persone you won't like it for sure.
It reminds me CMR series, which I always loved. I'm having more fun with this game than I had with DIRT2.