That is the main thing that i hate about it.
I wanted to get one and had a go for 10 mins at the Apple store.
General aesthetics - Excellent
Built quality - Excellent
Value for money - Bad
Ergonomics - Zero, form over function
The clicking is fine, I can even live with the lifting index finger for right click. I can't however and i challenge anyone that can, do the 2 finger swipe with 100% success rate without holding onto the mouse. And if you hold onto the mouse with your thumb and ring finger, you don't get get enough of the swipe movement for it to pick it up. And in the 10 mins that i tried doing that, i gave myself minor wrist strain ! Seriously, my hand was aching for the rest of the day. Sure, i could use it without that function, but then i am paying all that money and then missing out on a bunch of features that my Logitech Revolution has, the one function that i gain is going to break my wrist...for the pleasure of Steve Jobs getting my £55? No thanks.
It's a mouse that unless you REALLY wanted that mouse for its looks, there are many many better mouse out there on the market.