i have the e60 - that serves me quite well. if apple would bring back the newton i would readily spent a fortune to get it. But - i don't believe in devices which are supposed to do everything - being a phone, play 4000 songs, play video, a reasonable size&quality display, touchscreen, show pdfs, make life easier, control your hifi, etc... and being small, run 300 hours on battery and fits in your pocket... thats never supposed to happen - and how boring it would be - imagine everybody running around with a macbook in stylish "wraps", iPhone and/or iPod and using a macMini besides their tv.
So my point is: Apple has open up iSync to allow others to extend it - maybe they just wait until their iPhone has hit the market. But no one is served with 20 different address sync applications. If apples ignorance (just look at the iSync compatibility list - a joke!) is at least good enough to force mobile vendors to keep their stuff marginally compatible to iSync - then OK. But i doubt it.
but i will play around with it and learn - i just dont need to have iSync running with the M600i - but i would love it!
and - i do not love the apple hardware (never did) but the software in it (since the nextstep times)