Wow, I really did not expect that news!
For me the question is now: Who replaces him during the Monaco weekend?
I have been saying this for years. F1 will slowly lose the great ones (stuck in crap machines) to IndyCar, which is on a serious upswing. Drivers want to race, not manage a spaceship. While F1 is "the pinnacle" of motor racing, it's far from the pinnacle of driving. Kimi maybe next. Sainz then, if they don't wise up about how good he is (he was the ONLY one to make the call for slicks in China), and don't be shocked to hear Vettel either.
My respect for Alonso has been rising because he speaks his mind, gets more out of a car than 99% of all drivers, and is the best looking man on earth (according to my wife). I suspect this is possible because of Liberty, after McLaren. This will be tremendous for IndyCar, as world attention from oval-haters may convert a few. And it will be great for F1 because it will send a message -- drivers need to be more of the focus.
And so the F1 exit strategy begins. Pretty cool news though for Alonso and IndyCar fans. Lets hope the GP2 engine runs well on ovals.
He's running the McLaren?
Should be good in the corners, but 683 passes vs. being passed 21 times is going to be tough to manage. Seriously though, this is incredibly good for motorsport in general. Cross-pollination among various motorsport is badly needed (like the DTM and RallyCross do), and Andretti is the bridge (Rossi, his Dad, Mansell, Formula E). I agree completely Bram...don't be shocked to see Vettel, Sainz (if they don't wake up to his talent), and Hamilton (who loves it here) to be next.
Big difference, of course, is that these Indy 500 cars are not the same configuration they use for road racing, except the engine, and even that is tuned far differently for Indy. They are very very different. Heavier, lower, faster top end, taller gears, and virtually no downforce. The Indy 500 is not the best place to judge simply a driver alone, but someone of Alonso's character has already proven the rest. I'm so happy I want to kiss the man. And I have given my wife a "free pass" is she ever meets him.
How much is an Indycar driver earning these days?
If you look into it, you will find that they average about the same as F1 drivers, and the gap from rich to poor is much less. They stick with and value drivers in IndyCar, sometimes to their detriment. Not as many T-Shirt sales as old man Max has generated, but the racing is far far closer. The top four at Long Beach were separated by 1/10th of a second.