It's not groundbraking. At the time the iPhone was announced, I still used a Sony Ericsson 530i. And that was a normal mobile phone back then (nothing fancy, just normal). And although the software on the iPhone was basically just a browser (even without copy/paste, which amused me to no end), it was a browser that displayed proper HTML, not that mangled mess you got from Symbian phones.

Compare this to Linux: It started out very obscure, lagged behind in usability for years and finally managed to catch up. But now, at this point, everyone is so used to Windows (including the crap) that the general response is "meh, it's good enough". Plus, no Linux driven company will ever start a marketing campaign that comes anywhere near what Apple did back in the day.

Edit: Also, since you mentioned BB: From my perspective, they also never did usability right. Before the iPhone, Nokia was the usability king (at least in my circle of usage), but Ericsson and BB weren't that bad compared to them. That changed rapidly after capacitive touchscreens were widespread in consumer grade electronics.

Perhaps because Gnome is a crap.