I agree with the comments about Formula One being boring and processional but whenever I have visited Italy, I have noticed that it is a big deal to them, and they are mad about Ferrari, so I can understand why Rossi may want to join in.
Go to any bar or cafe in Italy on a Sunday afternoon and there will be a crowd of men shouting at the TV and cheering on Ferrari.
There is also the challenge of winning a World Championship in F1 as well as Moto GP / 500 GP - only John Surtees has managed that so far.
As regards the TT, full respect to the guys that do it- they are a breed apart from the slick Moto GP racers but I can understand someone like Rossi not wanting to do it as its bloody dangerous.
I think Foggy was the last man to win a World Championship and the TT.
Guy