After checking Tiger, it didn't seem like a worthy upgrade for me. Only things I'd like is html composing in Mail.app and mostly, the ability of iSync 2.0 to sync with my Nokia 6670 phone. I'll take Tiger when I get a new computer that comes with it...
But, I was wondering if there was a way to 'upgrade' my iSync 1.5 to sync with my phone. I can exchange file to and from the phone via Bluetooth without problems, Salling Clicker works flawlessly but I can't sync my address book and iCal with it. Is there a file that makes the new phones compatible with iSync or I'd need the upgraded application (which probaly needs Tiger to run)?