No, it was announced at Macworld. CES is where the rest of the Tech industry makes their announcements.
It bugs me how in the keynote, Jobsy was comparing the iphone to existing smartphones, when it really doesn't fall under that category. Sure it has email, internet etc, but then, so does just about every mobile phone made in the last 5-6 years. The other thing is, it's not an open platform. Anyone can write an application for a Windows/Palm/Symbian-based Smartphone, but only Apple and the companies they have dealings with can make iphone programs.

Oh, and for anyone thinking it's a revolutionary design, think again. As with most Apple products, it's received way too much hype for not so much innovation.