I am able to write a review of the game before it comes out, because I bought it some time ago with the I.S.I. digital delivery system (€ 35)...now the games has finally come in stores (it deserved it) and it is even cheaper...so let's start yor engines...
First of all the game has been programmed with two things in mind: modders and on-line play. In fact the game is a very strong "base" for teams of modders who can create as many racing "series" as possible. And they did it! On the internet you can find lots and lots of Mods (aka modifications) about different championships and seasons like F1, WTC, DTM, Porsche, GP2, many street cars and so on...you'll find also already out of the dvd box the F1 BMW Sauber 2006 and 2007, the Nascar series and the F3000 cars.
On the multiplayer side two tumbs up! The on-line play is great...I play in a F1 league with other 20 drivers and there has never been lag or connection problems at all.
The quality of the graphics depend on the quality of the Mod, in general it is very good and the game is also very smooth with average fps always over 100 fps on my system with medium details (I use resolution 1440x900 with Conroe E6300 and x1950pro).
So if you like racing simulations (remember this is not an arcade, if you wanna really enjoy the game you will need a PC wheel as well) and wanna play against other people on-line, this is the best choice.