Polyphony Digital  has redefined the way we look at racing games.It has created the most successful racing series.Every detail in their games is just perfect.I was wondering what would it be if they created a game other than the GT series?It would surely be amazing.They spend atleast 3 years in developing games not like profit hungry developers like EA that release games every year without any improvement.It is nearly 5 years since they started developing GT5.I will definitely buy that game.

Do you think they can make a masterpiece of a game other that the GT series?

I definitely think they can.It would be the best game ever and would sell like hell.

Wouldn't it be awesome if they made a game with bikes!

Nah...

Most successful racing series?

I don't know which one is, but I bet Mario Kart trumps it (then again, GT is a massive selling franchise).

^ It's certainly close. The top ten is as follows:

1) GT - 10
2) MK - 9
3) GT - 8
4) MK - 7
5) MK - 6
6) GT - 5
7) GT - 4
8) MK - 3
9) MK - 2
10) NFS - 1

GT has first place, so it wins on that.
And if you add up the points, GT has 27, while MK has... 27.

ok, there are two different Gran Turismo games ahead of MKWii, so your list is not correct. Also, why do you have NFS listed as #10?

They made Omega Boost for the PS1! That game rocked hard!!

Yeah.. that was a nice game.. fun shooter! With a big Robot!!

I think I read something about them wanting to do RPG's of some sort after GT5 , turn based or mmorpg I can't remember too well.

Lemme find a link.

edit :

"
He also added that it would be his "dream" to take a break from making games about cars and develop an RPG "with a similar high quality as GT" - however it remains a more distant possiblity, he added as all 120 of Polyphony's employees are tied up making GT5, the final version of which might not be out until after 2009, he confessed"

http://www.developmag.com/news/29626/Polyphony-looks-to-PC-game-development

I believe you are right, Gran Turismo sells because of the amount of polish that goes into it. And in terms of the highest sales of a single game GT takes the cake:

GT 3: A-Spec comes in at 14.87m

while the MK series has:

Mario Kart DS at 12.66m and
Mario Kart Wii at 10.46m

This could of course change as MK:DS and MK:Wii I think both have a change at the big 15 while GT5 will suffer from the relativly smaller user base of the PS3.

Now if you compare GT and MK in terms of total sales the winner shifts sides:

MK Series Total: 54.16m
GT Series Total: 49.92m

These numbers are all based off of VGChartz data of course and  can be found:
Here and Here

Sorry, couldn't let that one stand :P

Anyway, with how much effort they put into each game, are you sure they have the time to make a non GT game?