Well we have 3 conflicting sources then!
You heard its gonna be on the Passat CC/Superb 2 chassis
Another guy says its gonna be based on the A4 chassis
I say its gonna be based on the A4 chassis, but the old A4 at that.
Cant remember where I got it from as it was such a long time ago.
However we can do some deductions
The next Toledo is going to be about the size of a A4, the Passat and superb however are larger vehicles, and are getting larger still in the next incarnation. Therefore I doubt it will be riding the same chassis as the Passat CC etc.
Now both I and a SEAT employee have heard it will be sitting on a Audi A4 chassis, and its the right size for it. Also at the time of it being developed SEAT was also positioned under and influenced by Audi, just like how Lamborghini still is. Therefore it would make sense that the next Toledo would have Audi DNA in it. It also ties in with the rumors I have heard of the next Ibiza (the sporty versions at least) having a very similar rear suspension setup to the upcoming Audi A1 which is built to rival the handling qualities of the mini.
However there is no chance in hell that SEAT would get to use Audi's latest A4 chassis wonder piece the MLP, and so fore we can deduct that most likely the next Toledo will be sitting on a modified A4 chassis, which really is not all to bad.
But then again what do I know, this could very well all be wrong, the new VW CEO martin winterkorn has changed a few things lately!
Not suggesting it wouldn't be great for it to be based on the Audi's' A4 platform B7,8,or9... Yet as the Current Passat & Superb came away from sharing this larger more expensive platform series it seems quite unlikely that VAG would authorize such a plan for Seat!!!